JPWO2018174250A1 - Prepreg and fiber reinforced composite materials - Google Patents

Abstract

It is the prepreg containing (A) component, (B) component, and (C) component, Comprising: The said (A) component is a reinforcement fiber base material, The said (B) component is an epoxy resin composition, The said (C) Component) is the component (c1) or the component (c2), the component (c1) contains polyamide particles and thermosetting polyimide particles, and the component (c2) is a true sphere of polyamide having a melting point of 140 to 175 ° C. Prepreg, containing particles of shape.

Description

The present invention relates to a prepreg and a fiber reinforced composite material.
The present application is Japanese Patent Application No. 2017-058507 filed on March 24, 2017, Japanese Patent Application No. 2017-058508 filed on March 24, 2017, and February 23, 2018 The priority is claimed based on Japanese Patent Application No. 2018-030289 filed in Japan, the contents of which are incorporated herein by reference.

  Fiber reinforced composite materials are widely used in the sports and leisure fields, automotive fields, aircraft fields, other general industrial fields and the like because they are light in weight, high in strength and high in rigidity. Recently, fiber reinforced composite materials that are lighter in weight, higher in strength and higher in rigidity are often used in the automotive field, the aircraft field and the like.

  The fiber reinforced composite material is a material having reinforcing fibers and a matrix resin as essential components. The fiber-reinforced composite material is an anisotropic material in which the strength and elastic modulus of the reinforcing fiber in the fiber axial direction are extremely high but the strength and elastic modulus in the direction perpendicular to the fiber axial direction are low.

  The fiber-reinforced composite material is produced, for example, by laminating a prepreg obtained by impregnating a non-hardened thermosetting resin composition on a reinforcing fiber base, thermoforming, and curing the thermosetting resin composition. When manufacturing a fiber-reinforced composite material, it is possible by using a prepreg using a woven fabric of reinforcing fibers or laminating by combining the fiber axial directions of prepregs using reinforcing fibers arranged in one direction in different directions. Control of physical properties in each direction of the fiber reinforced composite material which is an anisotropic material is performed.

  However, in a fiber-reinforced composite material produced by laminating prepregs, the fraction of reinforcing fibers in the interlayer region made of matrix resin in the vicinity of the surface of the laminated prepreg is small, and the orientation of reinforcing fibers on both sides of the interlayer region The stress tends to be concentrated in the interlayer region because Therefore, regarding the post-impact compressive strength and the like of the fiber-reinforced composite material, breakage in the interlayer region is dominant. Therefore, it is known that improving the strength of the reinforcing fiber does not lead to a drastic improvement such as post-impact compressive strength of the fiber-reinforced composite material. In particular, when a cured product of a thermosetting resin composition is used as a matrix resin, the cured product of the thermosetting resin composition has various advantages such as cost, productivity, and heat resistance, while having a drawback of poor toughness. Because of this, the toughness of the interlayer region of the fiber-reinforced composite material is also insufficient.

As a fiber-reinforced composite material in which the toughness in the interlayer region is improved, for example, the following ones have been proposed.
(1) A fiber-reinforced composite material in which fine particles of high toughness polyamide or the like are disposed in an interlayer region (Patent Documents 1 and 2).
(2) A specific fiber-reinforced composite material in which fine particles having a specific particle size distribution index, sphericity and glass transition temperature are disposed in an interlayer region, and an elastomer component is contained in a matrix resin (Patent Document 3).
(3) A fiber-reinforced composite material in which fine particles of high-toughness polyamide are disposed in an interlayer region to form a unique morphology, and a manufacturing method. (Patent Documents 4 and 5).
In recent years, the application of fiber reinforced composite materials to members having large and three-dimensional curved surface shapes such as aircraft structural materials and blades of wind turbines has been promoted. When a large-sized member or a member having a three-dimensional curved surface shape is loaded with tensile or compressive stress, an out-of-plane peeling stress is generated in the interlayer region of the fiber-reinforced composite material. Therefore, Mode I interlaminar fracture toughness and Mode II interlaminar fracture toughness, which suppress the progress of cracks generated in the interlaminar region of the fiber reinforced composite material, are important characteristics.

In the fiber-reinforced composite material of (1), since the interlaminar fracture toughness at the time of development is high due to the mode II interlaminar fracture toughness, the compressive strength after impact is high, and the damage due to the falling weight impact on the member surface is suppressed. However, the fiber-reinforced composite material of Patent Document 1 is not sufficiently considered with respect to the morphology of fine particles after molding and the interface properties of the fine particles and the matrix resin composition, and the enlargement of the member and the three-dimensional curved surface shape The mode I interlaminar fracture toughness and the mode II interlaminar fracture toughness necessary for such a complication are insufficient. Further, in the method for molding the prepreg of Patent Document 2 and the fiber-reinforced composite material thereof, the morphology related to the fine particles in the fiber-reinforced composite material is controlled by the melting point and the molding temperature of the fine particles arranged in the interlayer region. This imposes restrictions on the manufacturing conditions. In addition, since the interface properties between the fine particles and the matrix resin are not sufficiently considered, cracks generated by the peeling stress in the out-of-plane direction in the interlayer region of the fiber reinforced composite material propagate in the interface between the fine particles and the matrix resin. The effect of the arrangement of the fine particles can not be sufficiently obtained, and furthermore, the crack is transferred to the interface between the reinforcing fiber and the matrix resin when advancing the interface between the fine particles and the matrix resin composition.
The fiber-reinforced composite material of (2) has high mode II interlaminar fracture toughness effective for improving compressive strength after impact and high mode I interlaminar fracture toughness necessary for complication such as enlargement and three-dimensional curved surface shape. However, the morphology of the fine particles after molding and the interface properties of the fine particles and the matrix resin composition are not sufficiently considered, and depending on the production conditions of the fiber reinforced composite material, the interlayer region of the fiber reinforced composite material as in Patent Document 2 Since the cracks generated by the peeling stress in the out-of-plane direction can not stably stay in the interlayer region, the effect of the fine particle arrangement can not be obtained sufficiently.
In the patent document of (3), a fiber-reinforced composite material excellent in mode I interlayer fracture toughness and mode II interlayer fracture toughness is produced by arranging highly tough polyamide fine particles in an interlayer region to form a unique morphology. Methods are disclosed. However, the manufacturing conditions such as the curing temperature and the temperature rise rate are restricted, and sufficient mode I interlaminar fracture toughness and mode II interlaminar fracture toughness can not be exhibited unless the above-mentioned specific morphology can be formed.

Japanese Patent Application Laid-Open No. 63-162732 JP, 2009-286895, A International Publication No. 2012/102201 Japanese Patent Application No. 2017-206615 JP, 2016-199682, A

  An object of the present invention is to provide a prepreg and a fiber-reinforced composite material stably having excellent mode I interlaminar fracture toughness and mode II interlaminar fracture toughness regardless of manufacturing conditions such as a curing temperature and a temperature rise rate.

The present invention has the following aspects.
[1] A prepreg comprising a component (A), a component (B) and a component (C),
The above (A) is a reinforcing fiber base,
Said (B) is an epoxy resin composition,
The component (C) is the component (c1) or the component (c2),
The component (c1) contains polyamide particles and thermosetting polyimide particles,
The prepreg in which said (c2) component contains the particle | grains of a true-spherical shape of polyamide of 140-175 degreeC of melting | fusing point.
[2] The prepreg according to [1], wherein the component (C) is the component (c1).
[3] The component (C) is the component (c1),
The prepreg according to [1] or [2], wherein the mass ratio represented by [polyamide particles]: [thermosetting polyimide particles] is 60:40 to 95: 5.
[4] The component (C) is the component (c1),
The prepreg according to any one of [1] to [3], wherein the melting point of the polyamide particles in the component (c1) is 140 ° C. to 175 ° C.
[5] The component (C) is the component (c1),
The prepreg according to any one of [1] to [4], wherein the polyamide particles in (c1) are crystalline copolymerized nylon particles.
[6] The component (C) is the component (c1),
The prepreg according to any one of [1] to [4], wherein the polyamide particles in (c1) are particles of a true sphere shape consisting of a copolymer of nylon 12 and nylon 6.
[7] The prepreg according to [1], wherein the component (C) is the component (c2).
[8] The prepreg according to [7], wherein the spherical particles of polyamide having a melting point of 140 to 175 ° C. are crystalline copolymerized nylon particles.
[9] The prepreg according to [7], wherein the true-spherical particles of polyamide having a melting point of 140 to 175 ° C. are true-spherical particles consisting of a copolymer of nylon 12 and nylon 6.
[10] The component (C) is the component (c2),
The prepreg according to any of [1] and [7] to [9], wherein (c2) further comprises a thermosetting polyimide particle.
[11]
The component (C) is the component (c2),
The above (c2) further contains a thermosetting polyimide particle,
The prepreg according to any one of [1] and [7] to [10], wherein the thermosetting polyimide particles contain a chemical structure of the following general formula (1) or the following general formula (2).
(In formula (1), R represents a divalent linking group.)
[12] The prepreg according to any one of [1] to [11], wherein 70% by mass or more of the component (C) is present in the surface layer of the component (A).
[13] The prepreg according to any one of [1] to [12], wherein the component (A) contains a reinforcing fiber, and the reinforcing fiber is a carbon fiber.
[14] The component (B) contains an epoxy resin and an aromatic polyamine,
The epoxy resin contains an epoxy resin having a naphthalene skeleton,
The prepreg according to any one of [1] to [13], wherein the content of the epoxy resin having a naphthalene skeleton is 60 to 100% by mass with respect to the total mass of the epoxy resin.
[15] The prepreg according to any one of [1] to [14], wherein the content of the component (C) is 5 to 25 parts by mass with respect to 100 parts by mass of the component (B).
[16] A fiber-reinforced composite material obtained by laminating two or more sheets of the prepreg according to any one of [1] to [15] and heating the same at a curing temperature of the component (B) or more.
[17] A fiber-reinforced composite material comprising the (A) component, the (B ') component and the (C) component,
The component (A) is a reinforcing fiber base,
The component (B ') is a cured product of an epoxy resin composition,
The component (C) is the component (c1) or the component (c2),
The component (c1) contains polyamide particles and thermosetting polyimide particles,
The component (c2) includes particles of a true sphere shape of polyamide having a melting point of 140 to 175 ° C.,
A fiber reinforced composite material, wherein a plurality of the component (A) is laminated, and the component (C) is present between layers of the component (A).

[18] The component (B) contains an epoxy resin,
The prepreg according to any one of [1] to [15], wherein the epoxy resin contains an epoxy resin having an oxazolidone ring skeleton.
[19] The prepreg according to [18], wherein the proportion of the epoxy resin having an oxazolidone ring skeleton is 10 to 40% by mass with respect to 100% by mass of the epoxy resin in the component (B).
[20] The component (B) contains an aromatic polyamine,
The prepreg according to any one of [1] to [15], [18], and [19], wherein the aromatic polyamine is 4,4′-diaminodiphenyl sulfone.
[21] The component (B) contains an epoxy resin,
[1] to [15], and [1], wherein the epoxy resin comprises at least one epoxy resin selected from the group consisting of bisphenol A epoxy resin, bisphenol F epoxy resin, and trifunctional or higher epoxy resin. The prepreg as described in 18] to [20].

  According to the present invention, it is possible to provide a prepreg and a fiber-reinforced composite material stably having excellent mode I interlaminar fracture toughness and mode II interlaminar fracture toughness regardless of manufacturing conditions such as a curing temperature and a temperature rising rate.

It is a torn surface SEM image (The aspect which the interface of (C) component is exposed) of the fiber reinforced composite material in a DCB test. It is a torn surface SEM image (the aspect in which the interface of (C) component is not exposed) of the fiber reinforced composite material in a DCB test. It is a top view of the molding board for evaluation used in the Example.

Hereinafter, the fiber-reinforced composite material according to an embodiment of the present invention, and the method for producing the same will be described in more detail.
The prepreg of the present invention is a prepreg containing the following components (A), (B) and (C).
(A) Component: Reinforcing Fiber Base Material (B) Component: Epoxy Resin Composition (C) Component: Component (c1) or Component (c2), wherein Component (c1) is a polyamide particle and a thermosetting polyimide particle (C2) component contains the particle | grains of a true-spherical shape of the polyamide of melting | fusing point 140-175 degreeC.
The fiber-reinforced composite material of the present invention is a fiber-reinforced composite material including the cured product of the component (A), the cured product of the component (B ') and the component (C), and a plurality of the component (A) is laminated And a fiber-reinforced composite material in which the component (C) is present in the surface layer of the component (A).
Furthermore, the fiber reinforced composite material of the present invention is a cured product of a laminate in which two or more of the above prepregs are laminated.

<Definition>
The terms used in the present invention and in the description of the present invention are as follows.
The "crystalline polyamide resin" means a resin whose melting point appears in differential scanning calorimetry (hereinafter referred to as DSC).
"Amorphous polyamide resin" means a resin whose melting point does not appear in DSC.
"Interlayer" means a region in the fiber-reinforced composite material produced by laminating prepregs, in which the fraction of reinforcing fibers in the vicinity of the boundary between the laminated prepreg and the prepreg is small.
The term "spherical-shaped particles" means that the spherical particles have a minor axis and a major axis for 10 randomly selected particles using a scanning electron microscope (JSM-6390, manufactured by Nippon Denshi Co., Ltd.) It refers to particles that are measured, and the mean value of the ratio of the minor diameter to the major diameter of the ten particles (minor diameter / major diameter) is 0.95 or more.
The "melting point" is the melting peak temperature of the DSC curve of the crystalline resin obtained as follows. The crystalline resin was heated at 10 ° C./min from room temperature to about 30 ° C. above the expected melting point and held for 10 minutes at about 30 ° C. above the expected melting point. The crystalline resin was then cooled at 10 ° C./min to a temperature about 50 ° C. below the expected melting point. The crystalline resin was then heated at 10 ° C./min to a temperature about 30 ° C. above the expected melting point.
The "glass transition temperature" is the midpoint glass transition temperature determined from the DSC measurement of the non-crystalline resin as follows. The amorphous resin is heated at 10 ° C./min from room temperature to about 30 ° C. higher than the estimated glass transition temperature, and kept at about 30 ° C. higher than the estimated glass transition temperature for 10 minutes The The amorphous resin was quenched at a temperature of about 50 ° C. lower than the estimated glass transition temperature, and the amorphous resin was heated at a rate of 20 ° C./min to a temperature about 30 ° C. higher than the estimated glass transition temperature. At the transition point of the baseline according to the glass transition temperature of the obtained DSC curve, a straight line and a base that are equidistant in the vertical axis direction from the straight line extending the low temperature side baseline and the straight line extending the high temperature side baseline The point at which the curves of the transition portions of the line intersect is taken as the glass transition temperature.
The “average particle size” means a particle size (D50) corresponding to a cumulative frequency of 50% in a volume-based cumulative distribution obtained by particle size distribution measurement.
"Epoxy resin" means a compound having two or more epoxy groups in the molecule.
"Interlaminar fracture toughness" means the limit value of energy required to cause delamination cracks around a unit area.
"GIC" means Mode I interlaminar fracture toughness value at the early stage of crack growth.
"GIIC" means the mode II interlaminar fracture toughness value at the early stage of crack growth.
"Mode I" means a (opening) deformation mode in which the direction of crack opening displacement is each perpendicular to the crack plane.
"Mode II" means a (longitudinal shear form) deformation mode in which the direction of crack opening displacement is parallel to the crack plane and perpendicular to the crack front edge.
"Crack opening displacement" refers to the relative displacement of the upper and lower surfaces of the crack.

<Fiber-reinforced composite material>
The fiber reinforced composite material according to an embodiment of the present invention is a fiber reinforced composite material formed by laminating and curing two or more prepregs that satisfy a specific condition.

Prepreg
The prepreg contains (A) component, (B) component, and (C) component.

((A) ingredient)
The component (A) is a reinforcing fiber base and is preferably in the form of a sheet. The reinforcing fiber base may be one in which reinforcing fibers are arranged in a single direction, or one in which they are arranged in a random direction.
Examples of the form of the component (A) include a woven fabric of a reinforcing fiber, a nonwoven fabric, and a sheet in which long fibers of the reinforcing fiber are aligned in one direction.
Component (A) is a sheet comprising a bundle of reinforcing fibers in which long fibers are aligned in a single direction from the viewpoint of being able to form a fiber-reinforced composite material having a high specific strength and a high specific elastic modulus. Are preferred, and in view of ease of handling, it is preferable to be a woven fabric of reinforcing fibers.

The reinforcing fibers may be long fibers, and the long fibers may be in the form of strands. Also, the reinforcing fibers may be crushed (milled), long fibers, or strands of which have been cut (chopped).
Examples of the material of the reinforcing fiber include glass fiber, carbon fiber (including graphite fiber), aramid fiber, and boron fiber. The reinforcing fiber base is preferably a carbon fiber base from the viewpoint of mechanical properties and weight reduction of the fiber-reinforced composite material.

  The tensile strength of the carbon fiber according to ASTM D4018 is preferably 3500 MPa or more, more preferably 5000 MPa or more, and still more preferably 6000 MPa or more. The tensile modulus of elasticity is preferably 150 GPa or more, more preferably 200 GPa or more, and still more preferably 250 GPa or more.

  For example, when using a fiber reinforced composite material according to one embodiment as a structural material of an aircraft, it is preferable that carbon fibers used for the fiber reinforced composite material have high strand strength, according to ASTM D4018 of carbon fiber. The compliant strand strength is preferably 6000 MPa or more.

The fiber diameter of the carbon fiber is preferably 3 μm or more, and preferably 12 μm or less. If the fiber diameter of carbon fibers is 3 μm or more, carbon fibers move laterally and carbon fibers are rubbed, for example, in a process for processing carbon fibers, such as combs, rolls, etc., carbon fibers and roll surfaces, etc. It is difficult for carbon fibers to cut or fuzz when rubs with one another. For this reason, the fiber reinforced composite material of the stable intensity | strength can be manufactured suitably. Moreover, if the fiber diameter of carbon fiber is 12 micrometers or less, carbon fiber can be manufactured by a normal method. That is, it is preferable that the fiber diameter of carbon fiber is 3-12 micrometers.
The number of carbon fibers in the carbon fiber bundle is preferably 1,000 to 70,000.

((B) ingredient)
Component (B) is an epoxy resin composition.
The component (B) preferably contains an epoxy resin and a curing agent for the epoxy resin. The component (B) may optionally contain other components other than the epoxy resin and the curing agent.

Epoxy resin:
As the epoxy resin, a bifunctional or more epoxy resin having two or more epoxy groups in the molecule is usually used. As the epoxy resin, an epoxy resin having an oxazolidone ring skeleton is preferable from the viewpoint that the toughness can be improved while maintaining the heat resistance and the rigidity of the cured product of the component (B).

  As epoxy resin, bisphenol A type epoxy resin which is liquid at 25 ° C. and 25 ° C., from the point that it has relatively low viscosity and does not adversely affect the heat resistance, toughness and other properties of the cured product of component (B). One or both of the liquid bisphenol F-type epoxy resins are preferred.

  The epoxy resin is preferably either one or both of bisphenol A epoxy resin solid at 25 ° C. and bisphenol F epoxy resin solid at 25 ° C. from the viewpoint of imparting toughness to the cured product of component (B) .

  The epoxy resin is preferably a trifunctional or more epoxy resin having three or more epoxy groups in the molecule from the viewpoint of improving the heat resistance of the cured product of the component (B).

Epoxy resin having oxazolidone ring skeleton:
The epoxy resin having an oxazolidone ring skeleton is also referred to as a urethane-modified epoxy resin or an isocyanate-modified epoxy resin. Commercial products of the epoxy resin having an oxazolidone ring skeleton include EPICLON (registered trademark) TSR-400 manufactured by DIC, Epototh (registered trademark) YD-952 manufactured by Nippon Steel Sumikin Chemical Co., Ltd., and D. E. R. (Registered trademark) 858, LSA 3301 manufactured by Asahi Kasei E-Materials, and the like.

  5-70 mass% is preferable with respect to 100 mass% of all the epoxy resins in (B) component, and, as for the ratio of the epoxy resin which has oxazolidone ring frame, 10-60 mass% is more preferable. If the proportion of the epoxy resin having an oxazolidone ring skeleton is at least the lower limit value of the above range, the toughness can be sufficiently improved while sufficiently maintaining the heat resistance and the rigidity of the cured product of the component (B). If the proportion of the epoxy resin having an oxazolidone ring skeleton is not more than the upper limit value of the above range, the viscosity of the component (B) does not become too high, so that the handleability of the component (B) is good and the preparation of the prepreg is easy. , The tackiness and the drapability of the prepreg are improved.

Bisphenol A Epoxy Resin and Bisphenol F Epoxy Resin:
When an epoxy resin having a solid oxazolidone ring skeleton is used, the viscosity of the component (B) increases, so either a bisphenol A epoxy resin liquid at 25 ° C. or a bisphenol F epoxy resin liquid at 25 ° C. It is preferable to use one or both in combination.

Although the bisphenol F-type epoxy resin liquid at 25 ° C. is slightly inferior in heat resistance to the bisphenol A-type epoxy resin liquid at 25 ° C., the viscosity is lower than that of the liquid bisphenol A-type epoxy resin, and the component (B) is It is preferable from the point which can give comparatively high elasticity modulus to hardened | cured material of 1 ..

  As commercially available products of bisphenol A type epoxy resin which is liquid at 25 ° C., jER (registered trademark) 828 manufactured by Mitsubishi Chemical Corp., D. E. R. (Registered trademark) 331, Epotote (registered trademark) YD-128 manufactured by Nippon Steel Sumikin Chemical Co., Ltd., EPICLON (registered trademark) 850 manufactured by DIC Corporation, and the like.

  As commercially available products of bisphenol F-type epoxy resin which is liquid at 25 ° C., jER (registered trademark) 807 manufactured by Mitsubishi Chemical Corp., D. E. R. (Registered trademark) 354, Epototh (registered trademark) YD-170 manufactured by Nippon Steel Sumikin Chemical Co., Ltd., EPICLON (registered trademark) 830 manufactured by DIC, and the like.

  The total proportion of bisphenol A epoxy resin liquid at 25 ° C. and bisphenol F epoxy resin liquid at 25 ° C. is preferably 10 to 80% by mass with respect to 100% by mass of all epoxy resins in component (B), 20-60 mass% is more preferable. If the total proportion of the bisphenol A epoxy resin liquid at 25 ° C. and the bisphenol F epoxy resin liquid at 25 ° C. is equal to or more than the lower limit of the above range, the component (B) can have an appropriate viscosity The handleability of the component (B) can be improved, and the impregnation into the component (A) can be facilitated. If the ratio of the total of bisphenol A epoxy resin liquid at 25 ° C. and bisphenol F epoxy resin liquid at 25 ° C. is not more than the upper limit value of the above range, the viscosity of component (B) is prevented from becoming excessively low. Can be prevented, when a prepreg prepared by impregnating the component (B) into the component (A) is heated and cured, a large amount of the component (B) can be prevented from flowing out of the system, and a fiber-reinforced composite material The possibility of adversely affecting the shape and mechanical characteristics of the

  The bisphenol A type epoxy resin solid at 25 ° C and the bisphenol F type epoxy resin solid at 25 ° C have heat resistance compared to bisphenol A type epoxy resin liquid at 25 ° C and bisphenol F type epoxy resin liquid at 25 ° C. Although slightly reduced, it is possible to impart toughness to the viscosity control of the component (B) and the cured product of the component (B).

  Although bisphenol F-type epoxy resin solid at 25 ° C. is slightly inferior in heat resistance to bisphenol A-type epoxy resin solid at 25 ° C., it is preferable from the viewpoint that relatively high elastic modulus can be given to the cured product of component (B). .

  Commercial products of bisphenol A type epoxy resin solid at 25 ° C. include jER (registered trademark) 1001, jER (registered trademark) 1002, jER (registered trademark) 1003, jER (registered trademark) 1004, Nippon Steel Corp. Epototh (registered trademark) YD-903 manufactured by Sumikin Chemical Co., Ltd., EPICLON (registered trademark) 1050 manufactured by DIC, EPICLON (registered trademark) 2050, EPICLON (registered trademark) 3050, EPICLON (registered trademark) 4050 and the like.

  Commercial products of bisphenol F-type epoxy resin solid at 25 ° C. include jER (registered trademark) 4004 P, jER (registered trademark) 4005 P, jER (registered trademark) 4007 P, jER (registered trademark) 4010 P, manufactured by Mitsubishi Chemical Corporation, Nippon Steel Epototh (registered trademark) YD-2001 manufactured by Sumikin Chemical Co., Ltd., Epototh (registered trademark) YD-2004, and the like.

  The total proportion of bisphenol A epoxy resin solid at 25 ° C. and bisphenol F epoxy resin solid at 25 ° C. is preferably 1 to 60 mass% with respect to 100 mass% of all epoxy resins in the component (B), 5-40 mass% is more preferable. If the total proportion of bisphenol A epoxy resin solid at 25 ° C. and bisphenol F epoxy resin solid at 25 ° C. is at least the lower limit of the above range, sufficient toughness can be imparted to the cured product of component (B) . If the ratio of the total of bisphenol A epoxy resin solid at 25 ° C. and bisphenol F epoxy resin solid at 25 ° C. is not more than the upper limit value of the above range, the viscosity of component (B) is prevented from becoming excessively high. It is possible to prevent the deterioration of the handleability of the component (B) and the difficulty in impregnating the component (A).

Trifunctional or higher epoxy resin:
Examples of the trifunctional epoxy resin include triazine skeleton-containing epoxy resin, aminophenol type epoxy resin, aminocresol type epoxy resin and the like.

  Examples of the tetrafunctional or higher epoxy resin include diaminodiphenylmethane epoxy resin, cresol novolac epoxy resin, phenol novolac epoxy resin, and aromatic glycidyl amine epoxy resin.

  The proportion of the trifunctional or higher epoxy resin is preferably less than 50% by mass, and more preferably 5 to 40% by mass, with respect to 100% by mass of all epoxy resins in the component (B). If the proportion of the trifunctional or higher epoxy resin is in the above range, the reactivity of the component (B) can be made into an appropriate range, and the heat resistance of the cured matrix resin composition can also be improved. If the reactivity of the component (B) is in an appropriate range, the adhesion of the interface between the component (C) described later, particularly the component (C) and the component (B) is prevented from becoming too weak, and the component (C) is blended. The effect of imparting excellent interlaminar fracture toughness to the fiber-reinforced composite material can be sufficiently exhibited. Furthermore, if the ratio of the trifunctional or higher functional epoxy resin is in the above range, it can be suppressed that the crosslink density of the cured product of the component (B) is excessively high, and the toughness of the cured product of the component (B) is significantly reduced. Can also be suppressed.

Commercial products of trifunctional epoxy resin include jER (registered trademark) 630 manufactured by Mitsubishi Chemical Corporation, Araldite (registered trademark) MY0500, MY 0510, MY 0600, MY 0610 manufactured by HUNTSMAN, TEPIC (registered trademark) manufactured by Nissan Chemical Industries, Ltd. G, -S, -SP, -VL and the like can be mentioned. Commercial products of tetrafunctional or higher epoxy resins include jER (registered trademark) 604, 152, 154 manufactured by Mitsubishi Chemical Corporation, Araldite (registered trademark) MY720 manufactured by HUNTSMAN, YH434L manufactured by Nippon Steel & Sumikin Chemical, YDPN- 638, YDCN-700-7, EPICLON (registered trademark) N-740, N-770, N-775 and the like manufactured by DIC.
Among them, jER (registered trademark) 630 made by Mitsubishi Chemical Co., Ltd., which is an aminophenol type epoxy resin, Araldite (registered trademark) MY0500, MY 0510, MY 0600, MY 0610 made by HUNTSMAN or jER manufactured by Mitsubishi Chemical Co., Ltd. Registered trademark 604, Araldite (registered trademark) MY720 manufactured by HUNTSMAN, and YH 434L manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., by blending, the heat resistance and elasticity of the cured matrix resin without largely increasing the viscosity of the matrix resin composition. In addition to the above-mentioned point, diaminodiphenylmethane type epoxy resin is more preferable because it can increase the rate, and in addition, it does not excessively increase the water absorption of the cured matrix resin.

Other epoxy resin:
The component (B) is, if necessary, another epoxy resin such as bisphenol S type, naphthalene type, dicyclopentadiene type, resorcinol type, hydroquinone type, bisphenoxyethanol fluorene type, bisphenol fluorene type, biscresol fluorene type epoxy resin, etc. May be included.

Hardener:
The curing agent may be any one that can cure the epoxy resin.

  Examples of the curing agent include amines, acid anhydrides (carboxylic acid anhydrides), phenols (novolak resins etc.), mercaptans, Lewis acid amine complexes, onium salts, imidazoles and the like. The epoxy resin curing agent is preferably an aromatic polyamine, and more preferably diaminodiphenyl sulfone, from the viewpoint of the excellent heat resistance and toughness of the cured product of the component (B).

  The amount of curing agent added varies depending on the type of curing agent. When the curing agent is diamino diphenyl sulfone, the amount of diamino diphenyl sulfone added is preferably such that the number of active hydrogen equivalents of diamino diphenyl sulfone is 0.9 to 1.5 times that of one equivalent of the epoxy group of the epoxy resin. An amount of 1.1 to 1.3 times is more preferable. If the addition amount of diaminodiphenyl sulfone is within the above range, the heat resistance and toughness of the cured product of the component (B) are further excellent.

  Although 3,3'-diaminodiphenyl sulfone can obtain a cured product having higher elasticity as compared to 4,4'-diaminodiphenyl sulfone, the cured product has inferior heat resistance, or the below-mentioned The adhesion at the interface between the C) component, in particular the (C) component and the (B) component, may be weakened, and the interlaminar fracture toughness of the fiber-reinforced composite material may be lowered. 4,4'-Diaminodiphenyl sulfone is inferior in elasticity of the obtained cured product as compared to 3,3'-diaminodiphenyl sulfone, but is superior in heat resistance of the cured product and is the component (C) described below, in particular, The adhesion at the interface between the component (C) and the component (B) is not easily weakened, and in some cases, the interlaminar fracture toughness of the fiber-reinforced composite material can be expressed higher. Therefore, 3,3'-diaminodiphenyl sulfone is more preferable in applications where the compression properties of fiber reinforced composite materials are required, and 4,4'-diamino in applications where heat resistance and interlaminar fracture toughness of fiber reinforced composite materials are required. More preferred is diphenyl sulfone. Depending on the application, it is also possible to use 3,3'-diaminodiphenyl sulfone and 4,4'-diaminodiphenyl sulfone together.

Other ingredients:
Examples of other components that can be included in the component (B) include various known additives.

  Additives include block copolymers composed of thermoplastic elastomer, elastomer fine particles (excluding component (C)), core-shell type elastomer fine particles, acrylic resin, etc., compounds having one epoxy group in molecule, dilution Agents, inorganic particles (such as silica), carbonaceous components (such as carbon nanotubes), flame retardants (such as phosphorus compounds), defoamers, and the like. From the viewpoint of improving the toughness without reducing the heat resistance of the cured product of the component (B), the additive is preferably a block copolymer composed of core-shell type elastomer fine particles, an acrylic resin or the like.

  As a commercial product of core-shell type elastomer fine particles, Metabrene (registered trademark) manufactured by Mitsubishi Rayon Co., Ltd., staphyroid manufactured by Aika Kogyo Co., Ltd., Paraloid (registered trademark) manufactured by Dow Chemical Co., etc. may be mentioned.

  The core-shell type elastomer fine particles may be dispersed in advance in an epoxy resin. Commercially available products of core-shell type elastomer fine particle dispersed epoxy resin include Kaneace (registered trademark) manufactured by Kaneka Co., Ltd., Acreset (registered trademark) BP series manufactured by Nippon Shokuhin Co., Ltd., and the like. The core-shell type elastomer fine particle dispersed epoxy resin is preferably used not only because it facilitates the preparation of the component (B) but also because the dispersed state of the core-shell type elastomer fine particles in the component (B) can be improved.

Examples of commercially available products of block copolymers composed of acrylic resin and the like include Nanostrength (registered trademark) series manufactured by Arkema, such as Nanostrength (registered trademark) M52N and Nanostrength (registered trademark) M22N.
As the component (B), an epoxy resin composition containing an epoxy resin, an epoxy resin having 60 to 100 mass% having a naphthalene skeleton with respect to 100 mass% of the epoxy resin, and further containing an aromatic polyamine as a curing agent It can be mentioned. This (B) component may contain other components other than an epoxy resin and a hardening agent as needed. Hereinafter, the component (B) is an epoxy resin composition containing an epoxy resin, an epoxy resin having a naphthalene skeleton having 60 to 100% by mass with respect to 100% by mass of the epoxy resin, and further containing an aromatic polyamine as a curing agent. The case will be described.

Epoxy resin having naphthalene skeleton:
An epoxy resin is usually a bifunctional or more epoxy resin having two or more epoxy groups in the molecule, and an epoxy resin having a naphthalene skeleton has a naphthalene ring in the molecule and two or more epoxy It is a bifunctional or more epoxy resin having a group. An epoxy resin having a naphthalene skeleton compared with a normal bisphenol A epoxy resin or a bisphenol F epoxy resin can impart good heat resistance to a cured product because of its rigid skeleton.

Bifunctional epoxy resin having naphthalene skeleton:
The bifunctional epoxy resin having a naphthalene skeleton is a bifunctional epoxy resin having a naphthalene ring in the molecule and having two epoxy groups. As described above, the bifunctional epoxy resin having a naphthalene skeleton can impart good heat resistance to the matrix resin after curing because of its rigid skeleton. In general, unlike the polyfunctional epoxy resin used to impart heat resistance to the cured product, the crosslink density of the cured product is not increased, so the toughness of the matrix resin after curing may be reduced, or between the reinforcing fiber and the matrix resin. It is possible to prevent the adhesion of the interface from being lowered and the effect of the above-mentioned fine particle arrangement can not be sufficiently obtained. When a large amount of multifunctional epoxy resin is used, the amount of water absorption of the matrix resin after curing tends to increase, but the bifunctional epoxy resin having a naphthalene skeleton also prevents the amount of water absorption of the matrix resin after curing be able to. As a commercial item of bifunctional epoxy resin which has naphthalene frame, EPICLON (registered trademark) HP-4032D made from DIC, HP-4032 SS, etc. are mentioned.
The proportion of the bifunctional epoxy resin having a naphthalene skeleton is preferably 50 to 100% by mass, more preferably 55 to 90% by mass, and more preferably 60 to 85% by mass with respect to 100% by mass of all epoxy resins in the component (B). Is even more preferred. If the proportion of the bifunctional epoxy resin having a naphthalene skeleton is at least the lower limit of the above range, the toughness of the cured product of the component (B), the adhesion of the interface between the reinforcing fiber and the matrix resin, and the water absorption amount are maintained The heat resistance of the cured product can be sufficiently improved. In addition, since a bifunctional epoxy resin having a naphthalene skeleton is usually liquid, a thermoplastic resin soluble in an epoxy resin such as a solid epoxy resin or a polyethersulfone is used together to form the (B) component. The handling property is improved, the preparation of the prepreg is facilitated, and the tackiness and the drapability of the prepreg are improved.

3- to 4-functional epoxy resin having naphthalene skeleton:
The trifunctional to tetrafunctional epoxy resin having a naphthalene skeleton is a trifunctional to tetrafunctional epoxy resin having a naphthalene skeleton in the molecule and having three to four epoxy groups. As described above, the rigid skeleton of the 3- to 4-functional epoxy resin having a naphthalene skeleton can impart good heat resistance to the cured matrix resin, and the resin is also cured by increasing the crosslink density of the cured product. Good heat resistance can be imparted to the later matrix resin. As a commercial item of the 3-4 functional epoxy resin which has naphthalene frame, EPICLON (registered trademark) HP-4700 made by DIC Corporation, HP-4710, HP-4770, NC-7000L made by Nippon Kayaku Co., Ltd. NC-7300L etc. are mentioned.
The proportion of the 3- to 4-functional epoxy resin having a naphthalene skeleton is preferably 5 to 50% by mass, more preferably 10 to 40% by mass, with respect to 100% by mass of all epoxy resins in the component (B). % By weight is even more preferred. If the proportion of the 3- to 4-functional epoxy resin having a naphthalene skeleton is at least the lower limit value of the above range, the heat resistance of the cured product of the component (B) can be sufficiently improved. On the other hand, if it is below the upper limit value, the toughness of the cured product of component (B), the adhesion of the interface between reinforcing fiber and matrix resin, and the amount of water absorption can be sufficiently maintained, and the viscosity of component (B) does not become too high. Therefore, the handleability of the component (B) is good, the preparation of the prepreg is easy, and the tackiness and the drapability of the prepreg are improved.

Other epoxy resin:
The component (B) is, in addition to the epoxy resin having a naphthalene skeleton, an epoxy resin having an oxazolidone ring skeleton, a bisphenol A epoxy resin, a bisphenol F epoxy resin, a bisphenol S type, a triazine skeleton-containing epoxy resin, if necessary. Aminophenol type epoxy resin, aminocresol type epoxy resin, cresol novolac type epoxy resin, phenol novolak type epoxy resin, aromatic glycidyl amine type epoxy resin, dicyclopentadiene type, resorcinol type, hydroquinone type, bisphenoxyethanol fluorene type, bisphenol Other epoxy resins such as fluorene type and biscresol fluorene type epoxy resins may be included.

  10-40 mass% is preferable with respect to 100 mass% of all the epoxy resins in (B) component, as for the ratio of the epoxy resin which has oxazolidone ring frame, 10-35 mass% is more preferable, and 15-30 mass% is further more preferable. preferable. If the proportion of the epoxy resin having an oxazolidone ring skeleton is at least the lower limit value of the above range, while maintaining the heat resistance and the rigidity of the cured product of the component (B) sufficiently, the toughness or the interface between the reinforcing fiber and the matrix resin Adhesion can be improved. If the proportion of the epoxy resin having an oxazolidone ring skeleton is not more than the upper limit value of the above range, the viscosity of the component (B) does not become too high, so that the handleability of the component (B) is good and the preparation of the prepreg is easy. , The tackiness and the drapability of the prepreg are improved.

The bisphenol A type epoxy resin which is liquid at 25 ° C and bisphenol F type which is liquid at 25 ° C from the viewpoint of having a relatively low viscosity and not adversely affecting the heat resistance, toughness and other properties of the cured product of component (B). The epoxy resin can be effectively used to adjust the viscosity of the component (B). As commercially available products of bisphenol A type epoxy resin which is liquid at 25 ° C., jER (registered trademark) 828 manufactured by Mitsubishi Chemical Corp., D. E. R. (Registered trademark) 331, Epotote (registered trademark) YD-128 manufactured by Nippon Steel Sumikin Chemical Co., Ltd., EPICLON (registered trademark) 850 manufactured by DIC Corporation, and the like. As commercially available products of bisphenol F-type epoxy resin which is liquid at 25 ° C., jER (registered trademark) 807 manufactured by Mitsubishi Chemical Corp., D. E. R. (Registered trademark) 354, Epototh (registered trademark) YD-170 manufactured by Nippon Steel Sumikin Chemical Co., Ltd., EPICLON (registered trademark) 830 manufactured by DIC, and the like.
The bisphenol A type epoxy resin solid at 25 ° C and the bisphenol F type epoxy resin solid at 25 ° C have heat resistance compared to bisphenol A type epoxy resin liquid at 25 ° C and bisphenol F type epoxy resin liquid at 25 ° C. Although slightly reduced, it is possible to impart toughness to the viscosity control of the component (B) and the cured product of the component (B).

Commercial products of bisphenol A type epoxy resin solid at 25 ° C. include jER (registered trademark) 1001, jER (registered trademark) 1002, jER (registered trademark) 1003, jER (registered trademark) 1004, Nippon Steel Corp. Epototh (registered trademark) YD-903 manufactured by Sumikin Chemical Co., Ltd., EPICLON (registered trademark) 1050 manufactured by DIC, EPICLON (registered trademark) 2050, EPICLON (registered trademark) 3050, EPICLON (registered trademark) 4050 and the like.
Although bisphenol F-type epoxy resin solid at 25 ° C. is slightly inferior in heat resistance to bisphenol A-type epoxy resin solid at 25 ° C., it is preferable from the viewpoint that relatively high elastic modulus can be given to the cured product of component (B). . Commercial products of bisphenol F-type epoxy resin solid at 25 ° C. include jER (registered trademark) 4004 P, jER (registered trademark) 4005 P, jER (registered trademark) 4007 P, jER (registered trademark) 4010 P, manufactured by Mitsubishi Chemical Corporation, Nippon Steel Epototh (registered trademark) YD-2001 manufactured by Sumikin Chemical Co., Ltd., Epototh (registered trademark) YD-2004, and the like.
To further improve the heat resistance of the cured product of component (B), triazine skeleton-containing epoxy resin, aminophenol type epoxy resin, aminocresol type epoxy resin, cresol novolac type epoxy resin, phenol novolac type epoxy resin, aromatic A multifunctional epoxy resin such as glycidyl amine type epoxy resin may be included.

Aromatic polyamines:
The component (B) preferably contains an aromatic polyamine as a curing agent. By using an aromatic polyamine as a curing agent, a cured product having good heat resistance can be obtained.
As the aromatic polyamine, as a curing agent, there are diaminodiphenylmethane, diaminodiphenyl sulfone, metaxylene diamine, metaphenylene diamine, derivatives and isomers such as alkyl substituted products thereof, and the like. Among these, diaminodiphenyl sulfone is preferable because it can impart good heat resistance and toughness to the cured product of component (B).
The amount of curing agent added varies depending on the type of curing agent. When the curing agent is diamino diphenyl sulfone, the amount of diamino diphenyl sulfone added is preferably such that the number of active hydrogen equivalents of diamino diphenyl sulfone is 0.9 to 1.5 times that of one equivalent of the epoxy group of the epoxy resin. An amount of 1.05 to 1.4 times is more preferable, and an amount of 1.1 to 1.3 times is even more preferable. If the addition amount of diaminodiphenyl sulfone is within the above range, the heat resistance and toughness of the cured product of the component (B) are further excellent.
Although 3,3'-diaminodiphenyl sulfone can obtain a cured product having higher elasticity as compared to 4,4'-diaminodiphenyl sulfone, the cured product has inferior heat resistance, or the below-mentioned The adhesion at the interface between the C) component, in particular the (C) component and the (B) component, may be weakened, and the interlaminar fracture toughness of the fiber-reinforced composite material may be lowered. 4,4'-Diaminodiphenyl sulfone is inferior in elasticity of the obtained cured product as compared to 3,3'-diaminodiphenyl sulfone, but is superior in heat resistance of the cured product and is the component (C) described below, in particular, The adhesion at the interface between the component (C) and the component (B) is not easily weakened, and in some cases, the interlaminar fracture toughness of the fiber-reinforced composite material can be expressed higher. Therefore, 3,3'-diaminodiphenyl sulfone is more preferable in applications where the compression properties of fiber reinforced composite materials are required, and 4,4'-diamino in applications where heat resistance and interlaminar fracture toughness of fiber reinforced composite materials are required. More preferred is diphenyl sulfone. Depending on the application, it is also possible to use 3,3'-diaminodiphenyl sulfone and 4,4'-diaminodiphenyl sulfone together. Commercially available products of 3,3'-diaminodiphenyl sulfone include 3,3'-DAS manufactured by Mitsui Chemicals Fine Inc., and commercially available products of 4,4'-diaminodiphenyl sulfone include Seika Cure of Wakayama Seika Kogyo Co., Ltd. S is mentioned.

Other ingredients:
Examples of other components that can be included in the component (B) include various known additives.
Additives include thermoplastic resins soluble in epoxy resins such as polyether sulfone, elastomer fine particles (except for component (C)), core-shell type elastomer fine particles, block copolymers composed of acrylic resin, etc., molecules Examples thereof include compounds having one epoxy group, diluents, inorganic particles (such as silica), carbonaceous components (such as carbon nanotubes), flame retardants (such as phosphorus compounds), and defoamers. From the viewpoint of improving the toughness without reducing the heat resistance of the cured product of the component (B), the additive is preferably a block copolymer composed of core-shell type elastomer fine particles, an acrylic resin or the like.
As a commercial product of core-shell type elastomer fine particles, Metabrene (registered trademark) manufactured by Mitsubishi Rayon Co., Ltd., staphyroid manufactured by Aika Kogyo Co., Ltd., Paraloid (registered trademark) manufactured by Dow Chemical Co., etc. may be mentioned.
The core-shell type elastomer fine particles may be dispersed in advance in an epoxy resin. Commercially available products of core-shell type elastomer fine particle dispersed epoxy resin include Kaneace (registered trademark) manufactured by Kaneka Co., Ltd., Acreset (registered trademark) BP series manufactured by Nippon Shokuhin Co., Ltd., and the like. The core-shell type elastomer fine particle dispersed epoxy resin is preferably used not only because it facilitates the preparation of the component (B) but also because the dispersed state of the core-shell type elastomer fine particles in the component (B) can be improved.
Examples of commercially available products of block copolymers composed of acrylic resin and the like include Nanostrength (registered trademark) series manufactured by Arkema, such as Nanostrength (registered trademark) M52N and Nanostrength (registered trademark) M22N.

Preparation Method of Component (B):
The component (B) can be prepared by various known methods. Examples of the method for preparing the component (B) include a method in which each component is heated and kneaded with a planetary mixer or a kneader.

  When a particulate curing agent such as diaminodiphenyl sulfone is used as a curing agent, the particulate curing agent may coagulate to cause poor dispersion, so the particulate curing agent is prekneaded in a liquid epoxy resin. It is preferable to make it into a masterbatch. For pre-kneading, it is preferable to use a kneader such as a three-roll mill or a ball mill. By making a particulate curing agent into a masterbatch in advance, it is possible to suppress physical property unevenness and curing failure in the cured product of component (B) due to dispersion failure, and impregnation failure in component (A) of component (B).

((C) ingredient)
The component (C) is the component (c1) or the component (c2), and the component (c1) contains polyamide particles and thermosetting polyimide particles, and the component (c2) is a true sphere having a melting point of 140 to 175 ° C Containing polyamide particles.

(Polyamide particles of (c1) component and thermosetting polyimide particles)
(Polyamide particles of (c1) component)
The polyamide particles of the component (c1) impart better interlaminar fracture toughness to the fiber-reinforced composite material. The polyamide resin constituting the polyamide particles of the component (c1) is not particularly limited as long as it has an amide bond in the repeating structure. The polyamide resin may be polyamide resin particles composed of one kind of polyamide resin or polyamide resin particles composed of two or more kinds of polyamide resins. In the case of polyamide resin particles composed of two or more types of polyamide resins, each polyamide resin may be uniformly present in the particles or may be unevenly present as in a layer structure. The polyamide resin can be obtained, for example, by ring-opening polymerization of lactams, polycondensation of diamine and dicarboxylic acid, polycondensation of aminocarboxylic acid and the like. Specific examples of the polyamide resin include nylon 6, nylon 46, nylon 66, nylon 11, nylon 12, nylon 610, nylon 612, nylon 6 T, nylon 6 I, nylon 9 T, nylon M5 T, and Trocelamide by Daicel-Evonic Co. Examples thereof include polyamide resins containing an aromatic ring and an alicyclic ring such as (registered trademark) T5000 and Trogamide (registered trademark) CX7323.
In addition, any of crystalline polyamide resin and non-crystalline polyamide resin can be preferably used, and either crystalline polyamide resin or non-crystalline polyamide resin may be used alone or in combination.
As the polyamide particles of (c1), crystalline copolymerized nylon particles are preferable, and true spherical particles made of a copolymer of nylon 12 and nylon 6 are more preferable.
Commercially available polyamide resins include VESTOSINT series (VESTOSINT (registered trademark) 2158, VESTOSINT (registered trademark) 2159, etc.) manufactured by Daicel-Evonik, Grilamide (R) TR 90 NZ manufactured by Emskemy, Grilamide (R) TR 55 And TOROGAMID (registered trademark) CX7323 and TOROGAMID (registered trademark) T 5000 manufactured by Daicel Evonik.
The melting point of the polyamide particles is preferably 140 ° C to 175 ° C, and more preferably 155 to 170 ° C.
When the melting point of the polyamide particles is in the above range, the interface between the matrix resin and the polyamide particles can be sufficiently strengthened in the process of curing the prepreg, and a fiber-reinforced composite material having high interlaminar fracture toughness can be obtained. .

(Average particle diameter of polyamide particles of component (c1))
2-50 micrometers is preferable and, as for the average particle diameter of the polyamide particle of (c1) component, 5-35 micrometers is more preferable. When the average particle diameter of the polyamide particles is equal to or more than the lower limit value of the range, the polyamide particles are less likely to enter the component (A) when producing a prepreg. Therefore, it is easy to obtain a prepreg that satisfies the condition that 70% by mass or more of all the (C) components described below is present in the surface layer of the (A) component, and as a result, it is possible to impart better interlayer fracture toughness to the fiber reinforced composite material. The component (C) present in the surface layer can be determined with the uneven distribution rate described later. Moreover, the increase in the viscosity at the time of mixing (B) component and (C) component can be suppressed. If the average particle diameter of the polyamide particles is equal to or less than the upper limit of the above range, the component (C) in the fiber-reinforced composite material can be inhibited from impairing the straightness of the reinforcing fiber of the component (A). It is possible to suppress the deterioration of the mechanical properties of the fiber-reinforced composite material, and to keep the crack generated in the interlayer region of the fiber reinforced composite material in the interlayer region due to the peeling stress in the out-of-plane direction. In addition, when applying a mixture of the (B) component and the (C) component on the surface of a release paper with uniform thickness in the production of a prepreg, clogging may be caused by equipment such as a roll coater or a die coater. Is reduced.

(Thermosetting polyimide particles of (c1) component)
The polyimide resin which comprises the thermosetting polyimide particle of (c1) component is a high molecular compound which has an imide bond in a repeating structure. Among polyimide resins, those having a relatively low molecular weight of the main chain and having reactive end groups are thermosetting polyimide resins. Since the reactive terminal group is included, the interface properties between the thermosetting polyimide particles and the matrix resin can be strengthened in the fiber-reinforced composite material, and the effects of the thermosetting polyimide particles described later can be sufficiently expressed. be able to. A thermoplastic polyimide resin having a relatively large molecular weight and having substantially no reactive terminal group can not strengthen the interface properties with the matrix resin, and is relatively excellent in toughness as a thermosetting polyimide. And the effects of the thermosetting polyimide particles described later can not be sufficiently expressed.
A thermosetting polyimide resin which can be preferably used as a constituent resin of thermosetting polyimide particles is a thermosetting polyimide resin containing the chemical structure of the general formula (1), and more specifically benzophenonetetracarboxylic acid dianhydride ( Thermoset polyimide having nonphthalimidic carbon content prepared from BTDA), 4,4'-methylenedianiline (MDA), and 2,4-toluenediamine (TDA) and containing 90 to 92 percent aromatic carbon It is a resin. Examples of the commercially available thermosetting polyimide resin particles include P84 (registered trademark) Polyimide manufactured by HP Polymer.

(R in Formula (1) represents a divalent linking group.)

Examples of the divalent linking _{group, -Ph -, - Ph-CH} 2 -Ph- , and the like. Here, -Ph- represents a phenylene group.

  It is also a thermosetting polyimide resin containing a chemical structure of the general formula (2), and more specifically, a thermosetting polyimide resin prepared from pyromellitic dianhydride and 4,4'-diaminodiphenyl ether (c1 The thermosetting polyimide particles of the component can be preferably used. Examples of commercially available particles of the thermosetting polyimide resin include polyimide powder PIP series, PIP-3 and PIP-25 manufactured by Sanyo Micron Corporation.

  Commercially available thermoplastic polyimide resins which can not be preferably used as the polyimide resin constituting the thermosetting polyimide particles of the component (c1) include Matrimid (registered trademark) 5218 manufactured by Huntsman.

(Average particle diameter of (c1) component thermosetting polyimide particles)
2-50 micrometers is preferable and, as for the average particle diameter of the thermosetting polyimide particle of (c1) component, 5-35 micrometers is more preferable. If the average particle diameter of the thermosetting polyimide particles is equal to or more than the lower limit value of the above range, the component (C) hardly enters the component (A) when producing a prepreg. Therefore, it is easy to obtain a prepreg that satisfies the condition that 70% by mass or more of all the components (C) described above is present in the surface layer of the component (A). As a result, the fiber reinforced composite material can be provided with further excellent interlaminar fracture toughness. Moreover, the increase in the viscosity at the time of mixing (B) component and (C) component can be suppressed. Then, it is possible to prevent further aggregation and dispersion failure.
If the average particle diameter of the thermosetting polyimide particles is equal to or less than the upper limit value of the above range, the component (C) in the fiber-reinforced composite material can be inhibited from damaging the straightness of the reinforcing fiber of the component (A). Deterioration of mechanical properties of the reinforced composite material can be suppressed, and a peeling stress in the out-of-plane direction can hold a crack generated in an interlayer region of the fiber reinforced composite material in the interlayer region. In addition, when applying a mixture of the (B) component and the (C) component on the surface of a release paper with uniform thickness in the production of a prepreg, clogging may be caused by equipment such as a roll coater or a die coater. Is reduced.
The average particle diameter of the thermosetting polyimide particles of the component (c1) is preferably in the range of 0.5 to 10 times the average particle diameter of the polyamide particles of the component (c1). When the average particle diameter of the thermosetting polyimide particles of the component (c1) is larger than 0.5 times the average particle diameter of the polyamide particles of the component (c1), the polyamide particles of the component (c1) and the thermal particles of the component (c1) described later The effects of the combined use of the curable polyimide particles can be sufficiently exhibited. When the average particle diameter of the thermosetting polyimide particles of component (c1) is 10 times or less the average particle diameter of the polyamide particles of component (c1), the thickness of the interlayer region is more uniform, that is, the reinforcing fibers of component (A) Since the deterioration of the straightness can be suppressed, it is possible to suppress the deterioration of the mechanical properties of the fiber-reinforced composite material, or to hold the crack generated in the interlayer region of the fiber-reinforced composite material in the interlayer region by the peeling stress in the out-of-plane direction. Can do it.

(Effect of combined use of polyamide particles of component (c1) and thermosetting polyimide particles of component (c1))
In general, thermosetting polyimide resins are relatively poor in toughness, and can not provide superior interlaminar fracture toughness to fiber-reinforced composite materials when used alone. On the other hand, the crack generated in the interlayer region of the fiber reinforced composite material by the peeling stress in the out-of-plane direction has a property of progressing selectively in a portion having less toughness, for example, the interface between matrix resin and reinforcing fiber bundle. Therefore, when the conventional high toughness matrix resin and fine particles are disposed in the interlayer region, the cracks generated in the interlayer region gradually transfer to the interface between the matrix resin and the reinforcing fiber bundle, which has lower toughness, as it progresses. In fact, it was completely transferred from the interlayer region to the reinforcing fiber layer, and it was not possible to stably impart excellent interlayer fracture toughness. However, when thermosetting polyimide particles having poor toughness are disposed in the interlayer region of the fiber-reinforced composite material, the cracks generated in the interlayer region stably progress to the interlayer region (c1) component polyamide particles and (c1) component By using the thermosetting polyimide particles in combination, it is possible to stably advance the cracks generated in the interlayer region, to further advance the interlayer region, and further to impart interlayer fracture toughness by the addition of the polyamide particles of the component (c1). It can be stably obtained regardless of the morphology of the interlayer region of the composite material and the interface properties of the polyamide particles of the component (c1) and the matrix resin composition.

(Contents of polyamide particles of component (c1) and thermosetting polyimide particles of component (c1))
The total content of the polyamide particles of the component (c1) and the thermosetting polyimide particles of the component (c1) is 5 to 25 parts by mass, preferably 10 to 25 parts by mass, with respect to 100 parts by mass of the component (B). 12-25 mass parts is more preferable, and 15-20 mass parts is still more preferable. If the total of the content of the polyamide particles of the component (c1) and the thermosetting polyimide particles of the component (c1) is equal to or more than the lower limit value of the range, the polyamide particles of the component (c1) and the (c1) The amount of the component thermosetting polyimide particles is increased, and for the reasons described above, it is possible to stably impart excellent interlaminar fracture toughness to the fiber-reinforced composite material. If the content of the polyamide particles of the component (c1) is equal to or less than the upper limit value of the above range, a matrix comprising the component (B) contained in the prepreg, the polyamide particles of the component (c1) and the thermosetting polyimide particles of the component (c1) It can suppress that the (B) component which occupies in resin becomes low too much. That is, when producing a prepreg, it is possible to prevent the mechanical properties of the fiber-reinforced composite material from being deteriorated due to the lack of the component (B) or to prevent the viscosity of the matrix resin composition from becoming too high. The matrix resin composition can be sufficiently impregnated.

(Proportion of thermosetting polyimide particles in component (c1))
The proportion of the thermosetting polyimide particles in the component (c1) is preferably 10 to 40% by mass. If the proportion of the thermosetting polyimide particles is at least the lower limit value of the above range, the effects of the thermosetting polyimide particles can be sufficiently obtained, and the interlayer fracture toughness excellent in the fiber reinforced composite material is stabilized from the above reasons. Can be given. If the proportion of the thermosetting polyimide particles is equal to or less than the upper limit value of the above range, it is possible to suppress that the adverse effect of the thermosetting polyimide particles having poor toughness on the interlaminar fracture toughness of the fiber-reinforced composite material becomes large.

The proportion of the more preferable thermosetting polyimide particles largely depends on the combination of components. For example, when the interface between the (A) component and the (B) component is weaker, the crack generated in the interlayer region is more likely to progress to the interface between the (A) component and the (B) component. The proportion of the thermosetting polyimide particles is preferably 20 to 40% by mass relative to the total mass of the component (c1). On the other hand, when the interface between the components (A) and (B) is stronger, the cracks generated in the interlayer region are less likely to progress to the interface between the components (A) and (B). The proportion of the thermosetting polyimide particles is preferably reduced to 10 to 25% by mass with respect to the total mass of the component (c1). In addition, when the interface between the components (B) and (C) is weaker, cracks generated in the interlayer region are more likely to progress to the interface between the components (A) and (B), so the heat in the component (c1) The proportion of the curable polyimide particles is preferably 20 to 40% by mass relative to the total mass of the component (c1). On the other hand, when the interface between the components (B) and (C) is stronger, the cracks generated in the interlayer region are less likely to progress to the interface between the components (A) and (B). The proportion of the thermosetting polyimide particles is preferably reduced to 10 to 25% by mass with respect to the total mass of the component (c1). When it is the interface between the weak (A) component and the (B) component and is the interface between the weak (B) component and the (C) component, the proportion of the thermosetting polyimide particles in the (c1) component is (c1) It is preferable to further increase to 25 to 40% by mass with respect to the total mass of the components. When it is the interface between the strong (A) component and the (B) component and the interface between the strong (B) component and the (C) component, the proportion of the thermosetting polyimide particles in the (c1) component is (c1) It is preferable to make it further less with 10-20 mass% with respect to the total mass of a component. Here, that the interface between the (A) component and the (B) component is weak means that the strength of the fiber reinforced composite material in one direction (all reinforcing fibers are oriented in the same direction) according to ASTM D 790 in 90 ° bending test. Is less than 125 MPa.
The strong interface between component (A) and component (B) means that the strength in one direction (all reinforcing fibers are oriented in the same direction) of the fiber reinforced composite material in a 90 ° bending test is 125 MPa according to ASTM D 790. It says that it is above.
A weak interface between the components (B) and (C) means that the fracture surface of a DCB (Double Cantilever Beam) test of a fiber-reinforced composite material performed according to ASTM D5528 is a scanning electron microscope (SEM: Scanning Electron Microscope) And the interface of component (C) 30 is exposed as shown in FIG.
The strong interface between the (B) component and the (C) component means that the fracture surface of the DCB (Double Cantilever Beam) test of the fiber reinforced composite material performed according to ASTM D5528 is a scanning electron microscope (SEM: Scanning Electron Microscope) And the interface of the component (C) is not exposed as shown in FIG.

(C2) True-Spheroidal Polyamide Particles Having a Melting Point of 140 to 175 ° C. The polyamide particles are polyamide resins in the form of particles, and can impart better interlaminar fracture toughness to the fiber-reinforced composite material. The polyamide resin is a compound having an amide bond in the repeating structure. The polyamide resin may be a polyamide resin composed of one kind of polyamide resin or a polyamide resin composed of two or more kinds of polyamide resins. In the case of polyamide resin particles composed of two or more types of polyamide resins, each polyamide resin may be uniformly present in the particles or may be unevenly present as in a layer structure. The polyamide resin can be obtained, for example, by ring-opening polymerization of lactams, polycondensation of diamine and dicarboxylic acid, polycondensation of aminocarboxylic acid and the like. Specific examples of the polyamide resin include nylon 6, nylon 46, nylon 66, nylon 11, nylon 12, nylon 610, nylon 612, nylon 6 T, nylon 6 I, nylon 9 T, nylon M5 T, and Trocelamide by Daicel-Evonic Co. Examples thereof include polyamide resins containing an aromatic ring and an alicyclic ring such as (registered trademark) T5000 and Trogamide (registered trademark) CX7323. Commercially available polyamide resins include VESTOSINT series (VESTOSINT (registered trademark) 2158, VESTOSINT (registered trademark) 2159, etc.) manufactured by Daicel-Evonik, Grilamide (R) TR 90 NZ manufactured by Emskemy, Grilamide (R) TR 55 And TOROGAMID (registered trademark) CX7323 and TOROGAMID (registered trademark) T 5000 manufactured by Daicel Evonik.

  However, since the component (c2) contains true-spherical polyamide particles having a melting point of 140 to 175 ° C., a crystalline polyamide resin is preferably used as the polyamide resin of the component (c2). Specific examples of crystalline polyamide resins include nylon 6, nylon 46, nylon 66, nylon 11, nylon 12, nylon 610, nylon 612, nylon 6T, nylon 6I, nylon 9T, nylon M5T, but homopolymers are The polyamide resin of the component (C) is preferably a copolymer which can lower the melting point because of the inhibition of the crystallinity because most of the polyamide resin does not fall within the range of 140 to 175 ° C. because of its high crystallinity. Among them, crystalline copolymerized nylon particles are preferable, and true spherical particles made of a copolymer of nylon 12 and nylon 6 are more preferable. Copolymers of nylon 12 and nylon 6 mainly composed of nylon 12 have high toughness and low moisture absorption, and their melting point is lower than that of nylon 12, and they can be used in fiber reinforced composite materials under a wider range of molding conditions. It is preferable because toughness can be suitably imparted. The molar ratio of nylon 12 to nylon 6 in the copolymer of nylon 12 and nylon 6 is preferably 9.8: 0.2 to 6.5: 3.5 for nylon 12: nylon 6, 9.5 0.5 to 7: 3 is more preferable. In the copolymer of nylon 12 and nylon 6, when the amount of nylon 12 is more than 90 mol%, the melting point is not sufficiently lowered as compared to the melting point of nylon 12 and therefore suitable for fiber reinforced composite materials under a wide range of molding conditions There is a possibility that toughness can not be given. On the other hand, if the content of nylon 12 is less than 60 mol%, the effect of nylon 6 having a higher melting point than nylon 12 becomes large, and the melting point of the copolymer of nylon 12 and nylon 6 becomes high. There is a possibility that the fiber reinforced composite material can not be suitably toughened. A commercially available product of true sphere particles of a copolymer of nylon 12 and nylon 6 which can be suitably used is MW-330 manufactured by Sumika Environmental Co., Ltd.

(The shape of a true-spherical polyamide particle having a melting point of 140 to 175 ° C. of the component (c2))
The shape of the true-spherical polyamide particles having a melting point of 140 to 175 ° C. is true spherical. Specifically, true spherical particles are obtained by measuring the minor axis and the major axis of ten randomly selected particles using a scanning electron microscope (JSM-6390, manufactured by Nippon Denshi Co., Ltd.). It refers to particles in which the average value of the ratio of the minor axis to the major axis of the particles (minor axis / major axis) is 0.9 or more.

(Average particle diameter of true spherical polyamide particles having a melting point of 140 to 175 ° C. of the component (c2))
2-50 micrometers is preferable, as for the average particle diameter of the true-ball-shaped polyamide particle of 140-175 degreeC of melting | fusing point, 5-35 micrometers is more preferable, and 6-25 micrometers is still more preferable. If the average particle diameter of the true-spherical polyamide particles is equal to or more than the lower limit value of the above range, the component (C) hardly enters the component (A) when producing a prepreg. Therefore, it is easy to obtain a prepreg that satisfies the condition that 70% by mass or more of all the (C) components described below is present in the surface layer of the (A) component, and as a result, it is possible to impart better interlayer fracture toughness to the fiber reinforced composite material. Moreover, the increase in the viscosity at the time of mixing (B) component and (C) component can be suppressed. If the average particle diameter of the true-spherical polyamide particles is equal to or less than the upper limit value of the range, the component (C) in the fiber-reinforced composite material can be inhibited from impairing the straightness of the reinforcing fiber of the component (A), It is possible to suppress the deterioration of the mechanical properties of the fiber-reinforced composite material, and to hold the crack generated in the interlayer region of the fiber-reinforced composite material in the interlayer region by the peeling stress in the out-of-plane direction. In addition, when applying a mixture of the (B) component and the (C) component on the surface of a release paper with uniform thickness in the production of a prepreg, clogging may be caused by equipment such as a roll coater or a die coater. Is reduced.
In addition, it is preferable that (c2) of this invention further contains a thermosetting polyimide particle.

(Thermosetting polyimide particles that can be included in component (c2))
The thermosetting polyimide particles that can be included in the component (c2) are thermosetting polyimide particles that can be used together with the true spherical polyamide particles having a melting point of 140 to 175 ° C of the component (c2) as the component (C). Means The thermosetting polyimide particles that can be included in the component (c2) are thermosetting polyimide particles. The polyimide resin is a polymer compound having an imide bond in the repeating structure. Among polyimide resins, those having a relatively low molecular weight of the main chain and having reactive end groups are thermosetting polyimide resins. Because of having a reactive terminal group, the interfacial properties of the thermosetting polyimide particles and the matrix resin can be strengthened in the fiber-reinforced composite material, and the thermosetting polyimide can be included in the component (c2) described later. The effect of the particles can be sufficiently expressed. A thermoplastic polyimide resin having a relatively large molecular weight and having substantially no reactive terminal group can not strengthen the interface properties with the matrix resin, and is relatively excellent in toughness as a thermosetting polyimide. The effect of the thermosetting polyimide particles that can be included in the component (c2) described later can not be sufficiently exhibited.

  The thermosetting polyimide resin which can be preferably used as the thermosetting polyimide particles which can be included in the component (c2) is a thermosetting polyimide resin containing the chemical structure of the general formula (1), more specifically benzophenone tetramer Non-phthalimido carbon content prepared from carboxylic acid dianhydride (BTDA), 4,4'-methylenedianiline (MDA), and 2,4-toluenediamine (TDA) and containing 90 to 92 percent aromatic carbon A thermosetting polyimide resin. Examples of the commercially available thermosetting polyimide resin particles include P84 (registered trademark) Polyimide manufactured by HP Polymer.

(R in Formula (1) represents a divalent linking group.)

Examples of the divalent linking _{group, -Ph -, - Ph-CH} 2 -Ph- , and the like. Here, -Ph- represents a phenylene group.

  It is also a thermosetting polyimide resin containing a chemical structure of the general formula (2), and more specifically, a thermosetting polyimide resin prepared from pyromellitic dianhydride and 4,4'-diaminodiphenyl ether (c2 Can be preferably used as a component). As a particle | grains of the said thermosetting polyimide resin marketed, the polyimide powder PIP series made from Sanyo Micro Inc., for example, a PIP-3, PIP-25, are mentioned.

  Commercially available thermoplastic polyimide resins which can not be preferably used as thermosetting polyimide particles which can be included in the component (c2) include Matrimid (registered trademark) 5218 manufactured by Huntsman.

(Average particle size of thermosetting polyimide particles that can be included in component (c2))
The average particle diameter of the thermosetting polyimide particles that can be included in the component (c2) is preferably 2 to 50 μm, and more preferably 5 to 35 μm. If the average particle diameter of the thermosetting polyimide particles is equal to or more than the lower limit value of the range, the thermosetting polyimide particles are less likely to enter the component (A) when producing a prepreg. Therefore, it is easy to obtain a prepreg that satisfies the condition that 70% by mass or more of all the components (C) described above is present in the surface layer of the component (A). As a result, the fiber reinforced composite material can be provided with further excellent interlaminar fracture toughness. Moreover, the increase in the viscosity at the time of mixing (B) component and the said thermosetting polyimide particle can be suppressed. Then, it is possible to prevent further aggregation and dispersion failure.

  If the average particle size of the thermosetting polyimide particles is equal to or less than the upper limit value of the range, it is possible to suppress that the thermosetting polyimide particles in the fiber-reinforced composite material impair the straightness of the reinforcing fiber of the component (A). The deterioration of the mechanical properties of the fiber-reinforced composite material can be suppressed, and the tearing-off stress in the out-of-plane direction can keep the crack generated in the interlayer region of the fiber-reinforced composite material in the interlayer region. In addition, when a mixture of the component (B) and the thermosetting polyimide particles is applied to the surface of a release paper with a uniform thickness in the production of a prepreg, clogging is caused by equipment such as a roll coater and a die coater. It can be suppressed.

  The average particle size of the thermosetting polyimide particles is preferably in the range of 0.5 to 10 times the average particle size of the true sphere-shaped polyamide particles having a melting point of 140 to 175 ° C. When the average particle diameter of the thermosetting polyimide particles is larger than 0.5 times the average particle diameter of the true sphere shaped polyamide particles having a melting point of 140 to 175 ° C., the true sphere shaped polyamide particles having a melting point of 140 to 175 ° C. The effects of the combined use of the thermosetting polyimide particles can be sufficiently exhibited. Further, when the average particle diameter of the thermosetting polyimide particles is 10 times or less of the average particle diameter of the spherical spherical polyamide particles having a melting point of 140 to 175 ° C., the thickness of the interlayer region is more uniform, that is, the reinforcing fiber of component (A) It is possible to suppress the deterioration of the mechanical properties of the fiber reinforced composite material, or to suppress the cracks generated in the interlayer region of the fiber reinforced composite material by the peeling stress in the out-of-plane direction to the interlayer region. You can fasten it.

(Effect of combined use of thermosetting polyimide particles and true spherical polyamide particles having a melting point of 140 to 175 ° C. of the component (c2))
In general, thermosetting polyimide resins are relatively poor in toughness, and can not provide superior interlaminar fracture toughness to fiber-reinforced composite materials when used alone. On the other hand, the crack generated in the interlayer region of the fiber reinforced composite material by the peeling stress in the out-of-plane direction has a property of progressing selectively in a portion having less toughness, for example, the interface between matrix resin and reinforcing fiber bundle. Therefore, when the conventional high toughness matrix resin and fine particles are disposed in the interlayer region, the cracks generated in the interlayer region gradually transfer to the interface between the matrix resin and the reinforcing fiber bundle, which has lower toughness, as it progresses. In fact, it was completely transferred from the interlayer region to the reinforcing fiber layer, and it was not possible to stably impart excellent interlayer fracture toughness. However, when thermosetting polyimide particles having poor toughness are disposed in the interlayer region of the fiber-reinforced composite material, the cracks generated in the interlayer region stably advance in the interlayer region. The crack formed in the interlayer region is stably progressed through the interlayer region by using the polyamide particles in the spherical shape and the thermosetting polyimide particles in combination of the melting point 140 to 175 ° C. in a stable manner, and further the spherical shape of 140 to 175 ° C. Interlaminar fracture toughness can be imparted by the addition of polyamide particles, and therefore, it is stable regardless of the morphology of the interlayer region of the fiber-reinforced composite material and the interface properties of the true spherical polyamide particles having a melting point of 140 to 175 ° C and the matrix resin composition. Can be obtained.

(Content of true-spherical polyamide particles having a melting point of 140 to 175 ° C of the component (c2))
The content of truly spherical polyamide particles having a melting point of 140 to 175 ° C. is 5 to 25 parts by mass, preferably 10 to 25 parts by mass, and more preferably 12 to 25 parts by mass with respect to 100 parts by mass of component (B). Preferably, 15 to 20 parts by mass is even more preferable. If the content of the component (C) is at least the lower limit of the above range, the amount of the spherical spherical polyamide particles localized in the interlayer region increases, and the interlayer fracture toughness excellent for the fiber-reinforced composite material from the above-mentioned reason Can be stably applied. If the content of the truly spherical polyamide particles is not more than the upper limit value of the above range, the (B) component occupied in the matrix resin consisting of the (B) component and the (C) component contained in the prepreg becomes too low. It can be suppressed. That is, when producing a prepreg, it is possible to prevent the mechanical properties of the fiber-reinforced composite material from being deteriorated due to the lack of the component (B) or to prevent the viscosity of the matrix resin composition from becoming too high. The matrix resin composition can be sufficiently impregnated.

(Content of (c2) component spherical polyamide particles having a melting point of 140 to 175 ° C. and thermosetting polyimide particles)
When the component (c2) further contains a thermosetting polyimide particle, the total content of the true-spherical polyamide particles having a melting point of 140 to 175 ° C. and the thermosetting polyimide particle is 100 parts by mass of the component (B). It is 5 to 25 parts by mass, more preferably 10 to 25 parts by mass, more preferably 12 to 25 parts by mass, and still more preferably 15 to 20 parts by mass. If the total content of the spherical spherical polyamide particles having a melting point of 140 to 175 ° C. and the thermosetting polyimide particles is not less than the lower limit value of the above range, a spherical spherical polyamide having a melting point of 140 to 175 ° C. The amount of particles and thermosetting polyimide particles is increased, and for the reasons described above, excellent interlaminar fracture toughness can be stably imparted to the fiber-reinforced composite material. If the content of true sphere shaped polyamide particles having a melting point of 140 to 175 ° C. is below the upper limit value of the above range, the (B) component contained in the prepreg, true sphere shaped polyamide particles having a melting point of 140 to 175 ° C. and thermosetting It can suppress that the (B) component which occupies in matrix resin which consists of a polyimide particle becomes low too much. That is, when producing a prepreg, it is possible to prevent the mechanical properties of the fiber-reinforced composite material from being deteriorated due to the lack of the component (B) or to prevent the viscosity of the matrix resin composition from becoming too high. The matrix resin composition can be sufficiently impregnated.

(The proportion of the thermosetting polyimide particles in the content of the (c2) component, the spherical polyamide particles having a melting point of 140 to 175 ° C. and the thermosetting polyimide particles)
The ratio of thermosetting polyimide particles in the mixture of true-spherical shaped polyamide particles and thermosetting polyimide particles having a melting point of 140 to 175 ° C. 5-40 mass% is preferable with respect to the sum total of content of. If the proportion of the thermosetting polyimide particles is at least the lower limit value of the above range, the effect of the thermosetting polyimide particles can be sufficiently obtained, and the interlayer fracture toughness excellent in the fiber reinforced composite material from the above-mentioned reason It can be stably applied. If the ratio of the thermosetting polyimide particles is equal to or less than the upper limit value of the range, it is possible to suppress that the adverse effect of the thermosetting polyimide particles having poor toughness on the interlaminar fracture toughness of the fiber-reinforced composite material becomes large.

  The proportion of the thermosetting polyimide particles more preferably depends largely on the combination of components. For example, when the interface between the (A) component and the (B) component is weaker, the crack generated in the interlayer region is more likely to progress to the interface between the (A) component and the (B) component. It is preferable to make more the ratio of 20-40 mass%. On the other hand, when the interface between the (A) component and the (B) component is stronger, the cracks generated in the interlayer region are less likely to progress to the interface between the (A) component and the (B) component. It is preferable to reduce the ratio of 5 to 25% by mass. In addition, when the interface between the component (B) and the spherical spherical polyamide particles having a melting point of 140 to 175 ° C. is weaker, cracks generated in the interlayer region are more likely to progress to the interface between the components (A) and (B). The proportion of the thermosetting polyimide particles is preferably 20 to 40% by mass. On the other hand, when the interface between the component (B) and the truly spherical polyamide particles having a melting point of 140 to 175 ° C. is stronger, the cracks produced in the interlayer region are less likely to progress to the interface between the components (A) and (B). Therefore, the proportion of the thermosetting polyimide particles is preferably reduced to 5 to 25% by mass. In the case of the interface between the weak (A) component and the (B) component and the weak (B) component and the interface of true spherical polyamide particles having a melting point of 140 to 175 ° C., the ratio of the thermosetting polyimide particles is 25 It is preferable to further increase the amount to 40% by mass. When it is the interface between the strong (A) component and the (B) component and the strong (B) component and the (c2) true spherical polyamide particle having a melting point of 140 to 175 ° C., the thermosetting polyimide particles The proportion is preferably further reduced to 5 to 20% by mass.

  Here, that the interface between the (A) component and the (B) component is weak means that the strength of the fiber reinforced composite material in one direction (all reinforcing fibers are oriented in the same direction) according to ASTM D 790 in 90 ° bending test. Is less than 125 MPa. The interface between the component (B) and the spherical polyamide particles having a melting point of 140 to 175 ° C. and the interface between the components (B) and the thermosetting polyimide particles that can be included in the component (c2) are weak according to ASTM D5528 Of a sphere-shaped polyamide having a melting point of 140 ° to 175 ° C. by observing a fracture surface of a DCB (Double Cantilever Beam) test of the fiber-reinforced composite material of the present invention using a scanning electron microscope (SEM: Scanning Electron Microscope) The interface of the particles and the interface of the thermosetting polyimide particles are exposed.

(Fiber weight of prepreg)
(The content of reinforcing fibers per 1 m ^2: FAW) Fiber basis weight of the prepreg may be appropriately set according to the prepreg applications, usually 50 to 300 g / ^{m 2.}

(Resin content of prepreg)
25-50 mass% is preferable with respect to the total mass of a prepreg, and, as for the resin content rate (The ratio of the sum total of (B) component and (C) component) in a prepreg, 30-40 mass% is more preferable. If the resin content in the prepreg is at least the lower limit value of the above range, it is possible to suppress that the tack of the prepreg becomes too low, and to make the tack suitable for handling. Furthermore, it is also possible to prevent the deterioration of the mechanical properties of the fiber reinforced composite material due to the lack of the component (B). If the resin content in the prepreg is not more than the upper limit value of the above range, it is possible to suppress that the tack of the prepreg becomes too high, and to make the tack suitable for handling. Furthermore, it is also possible to prevent the deterioration of the mechanical properties of the fiber-reinforced composite material accompanying the improvement of Vf (volume ratio of reinforcing fiber contained in the fiber-reinforced composite material) caused by the excess of the component (B).

(Thickness of prepreg)
The thickness of the prepreg may be appropriately set according to the use of the prepreg, and is usually 0.05 to 0.3 mm.
The thickness of the prepreg can be measured by a thickness gauge.

(Production method of prepreg)
The prepreg in the present invention can be manufactured by the method disclosed in Patent Document 2, its application, and the like.

As a method for producing a prepreg, the method (α) and the method (β) from the viewpoint of easily producing a fiber-reinforced composite material in which the component (C) is easily localized in the interlayer region and which satisfies the conditions (a) ), Method (γ) and method (δ) are preferred, and it is possible to more uniformly distribute the component (C) in the interlayer region more uniformly, and many (C) in the manufacturing process The method (γ) or the method (δ) is more preferable in that it can prevent the components from scattering and deteriorating the production environment.

Method (α):
In method (α), a resin film (F1) consisting of component (B) is laminated on one side or both sides of component (A), and component (A) is impregnated with component (B) to prepare base prepreg (P1). And (C) component is spread on one side or both sides of the base prepreg (P1).
The resin film (F1) can be produced by coating the component (B) on the surface of a release paper or the like. Examples of the method for impregnating the component (B) with the component (A) include known methods such as heating and pressing with a heating press roll.

Method (β):
In method (β), a resin film (F1) consisting of component (B) is laminated on one side or both sides of component (A), and component (A) is impregnated with component (B) to produce base prepreg (P1). The resin film (F2) in which the component (C) is dispersed on the surface of the component (B) is bonded to one side or both sides of the base prepreg (P1).

  The resin film (F1) and the base prepreg (P1) can be produced in the same manner as the method (α). The resin film (F2) can be produced by coating the component (B) on the surface of a release paper or the like and dispersing the component (C) on the surface of the component (B).

  Examples of the method for bonding the resin film (F2) to the base prepreg (P1) include known methods such as heating and pressing with a heating press roll. When the temperature is too high, most of the component (B) contained in the resin film (F2) is impregnated in the component (A) of the base prepreg (P1), and the tackiness of the prepreg is almost lost, and the fiber reinforced composite material Problems can arise in the manufacture of If the pressure is too high, most of the component (C) contained in the resin film (F2) will intrude into the component (A) of the base prepreg (P1) and the straightness of the reinforcing fiber may be impaired, (A The component (C) is almost lost on the surface of the component).

The component (B) contained in the base prepreg (P1) and the component (B) contained in the resin film (F2) may have the same resin composition or different resin compositions.
The content of the component (B) in the base prepreg (P1) may be lower than that of the method (α) due to the nature of the method (β) of bonding the resin film (F2) to the base prepreg (P1). preferable.

Method (γ):
In the method (γ), a resin film (F1) consisting of the component (B) is laminated on one side or both sides of the component (A), and the component (A) is impregnated with the component (B) to prepare a base prepreg (P1). The resin film (F3) containing the components (B) and (C) is bonded to one side or both sides of the base prepreg (P1).
The base prepreg (P1) can be produced in the same manner as the method (α).

  The resin film (F3) can be produced by applying a mixture of the components (B) and (C) on the surface of a release paper or the like.

  Examples of the method for bonding the resin film (F3) to the base prepreg (P1) include known methods such as heating and pressing with a heating press roll. When the temperature is too high, most of the component (B) contained in the resin film (F3) is impregnated into the component (A) of the base prepreg (P1), and the tackiness of the prepreg is almost lost, and the fiber reinforced composite material Problems can arise in the manufacture of If the pressure is too high, most of the component (C) contained in the resin film (F3) will intrude into the component (A) of the base prepreg (P1) and the straightness of the reinforcing fiber may be impaired, (A The component (C) is almost lost on the surface of the component).

  The component (B) contained in the base prepreg (P1) and the component (B) contained in the resin film (F3) may have the same resin composition or different resin compositions.

  The content of the component (B) in the base prepreg (P1) may be lower than that of the method (α) due to the nature of the method (γ) of bonding the resin film (F3) to the base prepreg (P1). preferable.

Method (δ):
In the method (δ), the resin film (F3) containing the (B) component and the (C) component, or the resin film (F3) containing the (B) component and the (C) component, is used as one side or both sides of the (A) component (B) component is impregnated into the (A) component.
The resin film (F3) can be produced in the same manner as the method (γ).

  The component (C) is filtered on the component (A), and the component (C) is localized near the surface of the prepreg. In order to filter the component (C) on the component (A), the average particle diameter of the component (C) is preferably larger than in the other methods. The average particle diameter of the polyamide particles of component (c1) and the spherical particles of polyamide having a melting point of 140 to 175 ° C. is preferably 5 to 50 μm, more preferably 10 to 50 μm, and still more preferably 15 to 50 μm. The average particle diameter of the thermosetting polyimide particles which can be contained in the thermosetting polyimide particles of the component (c1) and the component (c2) is preferably 15 to 50 μm, more preferably 20 to 50 μm, and further 25 to 50 μm. preferable.

<Fiber-reinforced composite material>
The fiber-reinforced composite material in the first aspect of the present invention is obtained by laminating two or more prepregs and heating at a curing temperature or more of the component (B) to cure the component (B).
The temperature at which the laminated prepreg is thermoformed may be any temperature that can appropriately cure the component (B), but the time required for curing the component (B) of the equipment used for the thermoforming From 170 to 190 ° C. is preferable. If the temperature at the time of thermoforming is 170 ° C. or higher, the component (B) is sufficiently cured, and a cured product having higher heat resistance can be obtained. If the temperature at the time of heat molding is 190 ° C. or less, it is possible to use less expensive equipment and auxiliary materials used for heat molding.

  Furthermore, the interface between the (B) component and the (C) component is further strengthened, and the crack generated in the interlayer region of the cured product is less likely to progress to the interface between the (A) component and the (B) component. When the component is crystalline, it is preferable to cure at a temperature higher than the melting point of the component (C), and when the component (C) is non-crystalline, it is cured at a glass transition temperature of the component (C).

  The heat molding time may be a time which can sufficiently cure the component (B) and which is suitable for a heat molding method described later. In the case of the autoclave molding method, the heat molding time is preferably 1 to 4 hours. If the heat molding time is one hour or more, curing of the component (B) is sufficient. If the thermoforming is more than 4 hours, the manufacturing cost becomes more expensive.

  Examples of the heat molding method include known methods such as an autoclave molding method, an oven molding method, and a press molding method. As a heat forming method, an autoclave forming method is preferable in that a fiber reinforced composite material having more excellent mechanical properties can be obtained.

The fiber-reinforced composite material in the second aspect of the present invention comprises (A) component, (B ') component and (C) component, (A) component is a reinforcing fiber base, and (B') component is A cured product of an epoxy resin composition, wherein component (C) is component (c1) or component (c2), component (c1) contains polyamide particles and thermosetting polyimide particles, and component (c2) has a melting point It contains particles of the spherical shape of polyamide at 140 to 175 ° C.
In the fiber-reinforced composite material according to the second aspect of the present invention, a plurality of the component (A) is laminated, and the component (C) is present between the layers of the component (A).
Examples of the component (A) and the component (C) include the same as the components (A) and (C) described in the explanation of the prepreg.
As the component (B ′), one obtained by curing the component (B) described in the explanation of the prepreg can be mentioned.
It is preferable to heat the (B) component to 170-190 degreeC as a method of hardening the (B) component. The heating time is preferably 1 to 4 hours.

  EXAMPLES Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited thereto.

<Physical Properties / Evaluation>
(Average particle size)
The average particle size of the resin particles was determined as follows.
The resin particles were subjected to particle size distribution measurement using a laser scattering type particle size measurement device (manufactured by JGC Corp., MODEL: 7340 Microtrac FRA) to obtain a cumulative distribution. The particle size (D50) at which the cumulative frequency on a volume basis in the cumulative distribution is 50% was taken as the average particle size.

(Fabrication of evaluation molded plate made of fiber reinforced composite material)
As shown in FIG. 3, 20 sheets of prepreg 2 were laminated so that the fiber axial direction of reinforcing fibers was aligned. In FIG. 3, the arrows indicate the fiber axis direction of the reinforcing fibers. Between the tenth prepreg 2 and the eleventh prepreg 2, a 50 μm thick fluororesin film 3 is placed between the 10th prepreg 2 and the 11th prepreg 2 so that the longitudinal direction is perpendicular to the fiber axial direction of the reinforcing fiber. The width 70 mm of the resin film 3 was sandwiched so as to overlap the prepreg 2. The laminated prepreg was covered with a vacuum bag so as not to have a gap. The laminated prepreg was heated from room temperature to 180 ° C. at a heating rate of 2 ° C./minute or 0.5 ° C./minute using an autoclave and held for 2 hours. The laminated prepreg was held in the autoclave at a temperature lowering speed of 3 ° C./min until it became 50 ° C. or less. The evaluation molding plate 1 was taken out of the autoclave. The pressure in the autoclave was 0.6 MPa from the start of heating until the removal.
(Distribution ratio of heat-deformed resin particles)
A test piece of 20 mm square was cut out from the molded plate for evaluation. The cross section of the test piece was polished using a polishing machine (REFINE-POLISHER APM-122, manufactured by Refinetech). A digital microscope (manufactured by KEYENCE, VHX-5000) was used to obtain a 500-fold enlarged photograph of the cross section of the test piece. From the photo, the thermally deformed resin particles in the interlayer region between the reinforcing fiber substrates and the thermally deformed resin particles in the reinforcing fiber substrate are cut out, and the mass of the cut out photo is measured, and localized from the following formula (3) The rate was calculated.
Distribution ratio = mass of thermally deformable resin particles present in the interlayer region / (mass of thermally deformed resin particles present in the interlayer region + mass of thermally deformable resin particles in the reinforcing fiber base) × 100 (Formula (S) 3)

(Measurement of GIC)
The GIC of the molded plate for evaluation was measured according to ASTM D5528 using an Instron universal tester (manufactured by Instron).

(Measurement of GIIC)
GIIC of the molded plate for evaluation was measured using an Instron universal tester (manufactured by Instron) in accordance with ASTM D7905.

<Raw material>
((A) ingredient)
(Reinforcing fiber bundle)
MR70: Carbon fiber bundle (PYROFIL (registered trademark) MR7012 P, manufactured by Mitsubishi Chemical Corporation, strand strength: 7000 MPa, fiber diameter of carbon fiber: 5 μm, number of carbon fibers: 12000).
((B) ingredient)
(Epoxy resin)
TSR-400: Epoxy resin having an oxazolidone ring skeleton (manufactured by DIC, EPICLON TSR-400).
jER 807: bisphenol F type liquid epoxy resin (manufactured by Mitsubishi Chemical Corporation, jER (registered trademark) 807).
jER 604: Diaminodiphenylmethane semisolid epoxy resin (Mitsubishi Chemical Corporation, jER (registered trademark) 604).
(Hardening agent)
Seikacure S: 4,4'-diaminodiphenyl sulfone (Wakayama Seika Kogyo Co., Ltd., Seikacure S).
(Optional ingredient)
E2020P: Polyether sulfone (manufactured by BASF Japan Ltd., ULTRASON (registered trademark) E2020 P SR MICRO).
((C) ingredient)
(Polyamide particles of (c1) component)
VESTOSINT 2158: polyamide 12 particles (manufactured by Daicel Evonik, VESTOSINT (registered trademark) 2158 natural, melting point: 177 ° C., average particle size: 21 μm).
(Thermosetting polyimide particles of (c1) component)
p84: thermosetting polyimide particles (manufactured by HP Polymer, P84 (registered trademark) Polyimide, average particle diameter: 17.7 μm).
PIP-3: thermosetting polyimide particles (manufactured by Sanyo Micron Corporation, polyimide powder PIP-3, average particle size: 2.8 μm).
PIP-25: thermosetting polyimide particles (manufactured by Sanyo Micron Corporation, polyimide powder PIP-25, average particle diameter: 12.9 μm).
(Resin particles not included in component (c1))
P84 NT1: Polyimide particles (manufactured by Daicel Evonik Co., polyimide P84 (registered trademark) NT1, average particle size: 8.9 μm).
P84 NT2: Polyimide particles (manufactured by Daicel Evonik Co., polyimide P84 (registered trademark) NT2, average particle diameter: 15.9 μm)

Example 1
(Preparation of (B) component)
To a planetary mixer, 35 parts by mass of TSR-400, 49 parts by mass of jER 807, 16 parts by mass of jER 604, and 2.8 parts by mass of E2020P were added. The jacket temperature of the planetary mixer was set to 140-160 ° C. and mixed until the raw materials became uniform. The contents were allowed to cool until the temperature of the contents reached 60 ° C. or less, and 40.6 parts by mass of Seikacure S was added to a planetary mixer. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain the component (B).

(Preparation of mixture (BC))
12.4 parts by mass of VESTOSINT 2158 and 6.2 parts by mass of p84 are added to 143.4 parts by mass of the component (B) in the planetary mixer, and the total content of VESTOSINT 2158 and p84 per 100 parts by mass of the component The proportion of p84 in the total content of 12.9 parts by mass and VESTOSINT 2158 and p84 was 33.5% by mass. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC).
(Preparation of prepreg)
A prepreg was produced by the method (δ).
The mixture (BC) was coated on the surface of the release paper with a uniform thickness using a hot melt coater to produce a resin film (F3).
A resin film (F3) is laminated on both sides of the component (A) in which a plurality of MR70s are aligned to form a sheet, and the component (A) is impregnated with the component (B) using a fusing press, The component (C) was filtered on the component (A), and the component (C) was localized near the surface of the prepreg to obtain a prepreg. Table 1 shows the composition of the prepreg and the preparation method.
(Manufacturing and evaluation of fiber reinforced composite materials)
A molded plate for evaluation was produced according to the method described above. The evaluation was performed on the molded plate for evaluation. The results are shown in Table 1.

Example 2
(Preparation of (B) component)
The component (B) was obtained in the same manner as in Example 1.
(Preparation of mixture (BC))
18.6 parts by mass of VESTOSINT2158 and 9.3 parts by mass of p84 are added to 143.4 parts by mass of the component (B) in the planetary mixer, and the total content of VESTOSINT 2158 and p84 per 100 parts by mass of the component (B) The proportion of p84 in the total content of 19.5 parts by mass and VESTOSINT 2158 and p84 was 33.3% by mass. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC).
(Preparation of prepreg)
As in Example 1, a prepreg was produced by the method (δ).
(Manufacturing and evaluation of fiber reinforced composite materials)
As in Example 1, a molded plate for evaluation was produced and evaluated. The results are shown in Table 1.

Example 3
(Preparation of (B) component)
The component (B) was obtained in the same manner as in Example 1.
(Preparation of mixture (BC))
14.3 parts by mass of VESTOSINT 2158 and 4.2 parts by mass of p84 are added to 143.4 parts by mass of the component (B) in the planetary mixer, and the total content of VESTOSINT 2158 and p84 per 100 parts by mass of the component (B) The proportion of p84 in the total content of 12.9 parts by mass and VESTOSINT 2158 and p84 was 22.7% by mass. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC).
(Preparation of prepreg)
As in Example 1, a prepreg was produced by the method (δ).
(Manufacturing and evaluation of fiber reinforced composite materials)
As in Example 1, a molded plate for evaluation was produced and evaluated. The results are shown in Table 1.

Example 4
(Preparation of (B) component)
The component (B) was obtained in the same manner as in Example 1.
(Preparation of mixture (BC))
16.5 parts by mass of VESTOSINT 2158 and 2.0 parts by mass of p84 are added to 143.4 parts by mass of the component (B) in the planetary mixer, and the total content of VESTOSINT 2158 and p84 with respect to 100 parts by mass of the component (B) The proportion of p84 in the total content of 12.9 parts by mass and VESTOSINT 2158 and p84 was 10.8% by mass. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC).
(Preparation of prepreg)
As in Example 1, a prepreg was produced by the method (δ).
(Manufacturing and evaluation of fiber reinforced composite materials)
As in Example 1, a molded plate for evaluation was produced and evaluated. The results are shown in Table 1.

Example 5
(Preparation of (B) component)
The component (B) was obtained in the same manner as in Example 1.
(Preparation of mixture (BC))
12.3 parts by mass of VESTOSINT 2158 and 6.2 parts by mass of PIP-3 are added to 143.4 parts by mass of the component (B) in a planetary mixer, and the total of VESTOSINT 2158 and PIP-3 per 100 parts by mass of the component (B) The content of PIP-3 was 12.9 parts by mass, and the ratio of PIP-3 to the total content of VESTOSINT 2158 and PIP-3 was 33.5% by mass. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC).
(Preparation of prepreg)
As in Example 1, a prepreg was produced by the method (δ).
(Manufacturing and evaluation of fiber reinforced composite materials)
As in Example 1, a molded plate for evaluation was produced and evaluated. The results are shown in Table 1.

Example 6
(Preparation of (B) component)
The component (B) was obtained in the same manner as in Example 1.
(Preparation of mixture (BC))
12.3 parts by mass of VESTOSINT 2158 and 6.2 parts by mass of PIP-25 are added to 143.4 parts by mass of the component (B) in the planetary mixer, and the total of VESTOSINT 2158 and PIP-25 per 100 parts by mass of the component (B) The ratio of PIP-25 in the total content of 12.9 parts by mass of VESTOSINT 2158 and PIP-25 was 33.5% by mass. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC).
(Preparation of prepreg)
As in Example 1, a prepreg was produced by the method (δ).
(Manufacturing and evaluation of fiber reinforced composite materials)
As in Example 1, a molded plate for evaluation was produced and evaluated. The results are shown in Table 1.

Comparative Example 1
(Preparation of (B) component)
The component (B) was obtained in the same manner as in Example 1.
(Preparation of mixture (BC '))
VESTOSINT 215 in 143.4 parts by mass of component (B) in a planetary mixer
18.6 mass parts of 8 were added, and content of VESTOSINT2158 with respect to 100 mass parts of (B) component was 13.0 mass parts. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC ′).
(Preparation of prepreg)
As in Example 1, a prepreg was produced by the method (δ).
(Manufacturing and evaluation of fiber reinforced composite materials)
As in Example 1, a molded plate for evaluation was produced and evaluated. The results are shown in Table 2.

Comparative Example 2
(Preparation of (B) component)
The component (B) was obtained in the same manner as in Example 1.
(Preparation of mixture (BC '))
12.4 parts by mass of VESTOSINT2158 and 6.2 parts by mass of P84NT1 are added to 143.4 parts by mass of the component (B) in the planetary mixer, and the total content of VESTOSINT 2158 and P84NT1 per 100 parts by mass of the component (B) The proportion of P84NT1 in the total content of 12.9 parts by mass and VESTOSINT2158 and P84NT1 was 33.5% by mass. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC ′).
(Preparation of prepreg)
As in Example 1, a prepreg was produced by the method (δ).
(Manufacturing and evaluation of fiber reinforced composite materials)
As in Example 1, a molded plate for evaluation was produced and evaluated. The results are shown in Table 2.

Comparative Example 3
(Preparation of (B) component)
The component (B) was obtained in the same manner as in Example 1.
(Preparation of mixture (BC '))
12.34 parts by mass of VESTOSINT2158 and 6.2 parts by mass of P84NT2 were added to 143.4 parts by mass of the component (B) in the planetary mixer, and the total content of VESTOSINT 2158 and P84NT2 per 100 parts by mass of the component (B) was added The proportion of P84NT2 in the total content of 12.9 parts by mass and VESTOSINT2158 and P84NT1 was 33.5% by mass. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC ′).
(Preparation of prepreg)
As in Example 1, a prepreg was produced by the method (δ).
(Manufacturing and evaluation of fiber reinforced composite materials)
As in Example 1, a molded plate for evaluation was produced and evaluated. The results are shown in Table 2.

Comparative Example 4
(Preparation of (B) component)
The component (B) was obtained in the same manner as in Example 1.
(Preparation of mixture (BC '))
18.6 parts by mass of P84 was added to 143.4 parts by mass of the component (B) in the planetary mixer, and the total content of P84 with respect to 100 parts by mass of the component (B) was 13.0 parts by mass. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC ′).
(Preparation of prepreg)
As in Example 1, a prepreg was produced by the method (δ).
(Manufacturing and evaluation of fiber reinforced composite materials)
As in Example 1, a molded plate for evaluation was produced and evaluated. The results are shown in Table 2.

The fiber-reinforced composite materials of Examples 1 to 6 exhibit GIIc of 2.0 kC / min or more and 1.0 kJ / m ² or more under any molding conditions at 2.0 ° C./min and 0.5 ° C./min, and show mode II interlaminar fracture toughness It was excellent. On the other hand, the fiber-reinforced composite materials of Comparative Examples 1 to 3 which do not contain a thermosetting polyimide particle show GIIc of less than 1.0 kJ / m ² under molding conditions of 0.5 ° C./min. inferior. Further, in Comparative Example 4 in which only thermosetting polyimide particles were contained, the temperature was 2.0 ° C./minute, 0.5 ° C./minute, and a low value of less than 1.0 kJ / m ² under any molding condition.
When Example 1 and Example 2 are compared, Example 2 showed higher GIIc containing more (C) components. From the viewpoint of expression of excellent mode II interlaminar fracture toughness, Example 2 is more preferable as the total of the content of the component (C) with respect to 100 parts by mass of the component (B).
Moreover, when Example 1 and Example 3, 4 are compared, GIIc of the shaping | molding conditions of 0.5 degree-C / min becomes high in order of Example 4, Example 3, and Example 1, and these implementation In the combinations of the components (A) to (C) in the example, the ratio of the thermosetting polyimide particles in the component (C) ((c1) polyamide particles and thermosetting polyimide particles) is higher than that in Example 4 compared with Example 3. Is preferred, and Example 1 is preferred over Example 3.
The fiber-reinforced composite material obtained by the method for producing a fiber-reinforced composite material of the present invention stably provides a fiber-reinforced composite material excellent in mode I interlaminar fracture toughness and mode II interlaminar fracture toughness regardless of manufacturing conditions. It is useful as aerospace applications, sports and leisure applications, automotive applications, and other general industrial applications (tendons).

<Raw material>
((A) ingredient)
(Reinforcing fiber bundle)
MR70: Carbon fiber bundle (PYROFIL (registered trademark) MR7012 P, manufactured by Mitsubishi Chemical Corporation, strand strength: 7000 MPa, fiber diameter of carbon fiber: 5 μm, number of carbon fibers: 12000).

((B) ingredient)
(Epoxy resin)
TSR-400: Epoxy resin having an oxazolidone ring skeleton (manufactured by DIC, EPICLON TSR-400).
jER 807: bisphenol F type liquid epoxy resin (manufactured by Mitsubishi Chemical Corporation, jER (registered trademark) 807).

jER 604: Diaminodiphenylmethane semisolid epoxy resin (Mitsubishi Chemical Corporation, jER (registered trademark) 604).
(Hardening agent)
Seikacure S: 4,4'-diaminodiphenyl sulfone (Wakayama Seika Kogyo Co., Ltd., Seikacure S).
(Optional ingredient)
E2020P: Polyether sulfone (manufactured by BASF Japan Ltd., ULTRASON (registered trademark) E2020 P SR MICRO).

((C) ingredient)
Polyamide particles of component (c2) MW-330: True spherical copolyamide particles (manufactured by Sumika Environmental Science Co., Ltd., MW-330, melting point: 166 ° C., average particle size: 8 μm, average value of minor axis / major axis: 0 .96).

(C2) Thermosetting polyimide particles that can be contained in component p84: thermosetting polyimide particles (manufactured by HP Polymer, P84 (registered trademark) Polyimide, average particle diameter: 18 μm).

(Resin particles not included in component (C))
VESTOSINT 2158: non-spherical polyamide 12 particles (manufactured by Daicel Evonik, VESTOSINT (registered trademark) 2158 natural, melting point: 177 ° C., average particle size: 21 μm, average value of minor axis / major axis: 0.65).
Ny 12 particles A: true spherical polyamide 12 particles (melting point: 177 ° C., average particle diameter: 21 μm, average value of minor axis / major axis: 0.94).
TR55: True spherical amorphous polyamide particles (Grillamide (registered trademark) TR55, manufactured by Emskiemy, melting point: 160 ° C., average particle size: 10 μm, average value of minor axis / major axis: 0.91).

<Preparation of Ny12 particle A>
True spherical polyamide 12 particles were produced according to the method for producing true spherical polyamide described in JP-A-10-316750.

Example 7
(Preparation of (B) component)
To a planetary mixer, 35 parts by mass of TSR-400, 49 parts by mass of jER 807, 16 parts by mass of jER 604, and 2.8 parts by mass of E2020P were added. The jacket temperature of the planetary mixer was set to 140-160 ° C. and mixed until the raw materials became uniform. The contents were allowed to cool until the temperature of the contents reached 60 ° C. or less, and 40.6 parts by mass of Seikacure S was added to a planetary mixer. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain the component (B).

(Preparation of mixture (BC))
37.2 parts by mass of MW-330 was added to 143.4 parts by mass of the component (B) in the planetary mixer, and the content of MW-330 was 100 parts by mass of the component (B) to 25.9 parts by mass. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC).

(Preparation of prepreg)
A prepreg was produced by the method (γ).

The component (B) and the mixture (BC) were respectively coated on the surface of a release paper with a uniform thickness using a hot melt coater to produce resin films (F1) and (F3).
A plurality of resin films (F1) are aligned to form a sheet of MR 70 and bonded to both sides of the component (A), and the component (A) is impregnated with the component (B) using a fusing press to make a base prepreg A prepreg was obtained by preparing (P1) and further laminating a resin film (F3) on both sides of the base prepreg (P1). The content of the component (C) with respect to 100 parts by mass of the component (B) of the obtained prepreg is 13.0 parts by mass. Table 4 shows the composition of the prepreg and the preparation method.

(Manufacturing and evaluation of fiber reinforced composite materials)
A molded plate for evaluation was produced according to the method described above. The evaluation was performed on the molded plate for evaluation. The results are shown in Table 4.

Example 8
(Preparation of (B) component)
The component (B) was obtained in the same manner as in Example 1.

(Preparation of mixture (BC))
33.0 parts by mass of MW-330 and 4.0 parts by mass of p84 are added to 143.4 parts by mass of component (B) in a planetary mixer, and the sum of MW-330 and p84 per 100 parts by mass of component (B) Content of 12.9 mass parts. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC).

(Preparation of prepreg)
In the same manner as in Example 7, a prepreg was produced by the method (γ). The content of the component (C) with respect to 100 parts by mass of the component (B) of the obtained prepreg is 12.9 parts by mass. Table 4 shows the composition of the prepreg and the preparation method.

(Manufacturing and evaluation of fiber reinforced composite materials)
As in Example 7, a molded plate for evaluation was produced and evaluated. The results are shown in Table 4.

Comparative Example 5
(Preparation of (B) component)
The component (B) was obtained in the same manner as in Example 7.

(Preparation of mixture (BC '))
18.6 parts by mass of VESTOSINT 2158 was added to 143.4 parts by mass of the component (B) in the planetary mixer, and the content of VESTOSINT 2158 was 13.0 parts by mass with respect to 100 parts by mass of the component (B). The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC ′).

(Preparation of prepreg)
A prepreg was produced by the method (δ).

The mixture (BC ′) was coated on the surface of the release paper with a uniform thickness using a hot melt coater to produce a resin film (F3).
A plurality of resin films (F3) are aligned to form a sheet of MR 70 and bonded to both sides of component (A), and component (B) is component (A) using a fusing press.
And the VESTOSINT 2158 was filtered on the component (A), and the VESTOSINT 2158 was localized near the surface of the prepreg to obtain a prepreg. The total content of VESTOSINT 2158 with respect to 100 parts by mass of the (B) component of the obtained prepreg is 13.0 parts by mass. Table 4 shows the composition of the prepreg and the preparation method.

(Manufacturing and evaluation of fiber reinforced composite materials)
As in Example 7, a molded plate for evaluation was produced and evaluated. The results are shown in Table 4.

Comparative Example 6
(Preparation of (B) component)
The component (B) was obtained in the same manner as in Example 7.

(Preparation of mixture (BC '))
12.4 parts by mass of VESTOSINT 2158 and 6.2 parts by mass of p84 are added to 143.4 parts by mass of the component (B) in the planetary mixer, and the total content of VESTOSINT 2158 and p84 per 100 parts by mass of the component (B) It was 12.9 parts by mass. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC ′).

(Preparation of prepreg)
A prepreg was produced by the method (δ).
The mixture (BC ′) was coated on the surface of the release paper with a uniform thickness using a hot melt coater to produce a resin film (F3).
A resin film (F3) is laminated on both sides of the component (A) in which a plurality of MR70s are aligned to form a sheet, and the component (A) is impregnated with the component (B) using a fusing press, VESTOSINT 2158 and p84 were filtered on the component (A), and VESTOSINT 2158 and p84 were localized near the surface of the prepreg to obtain a prepreg. The total content of VESTOSINT 2158 and p84 with respect to 100 parts by mass of the (B) component of the obtained prepreg is 12.9 parts by mass. Table 4 shows the composition of the prepreg and the preparation method.

(Manufacturing and evaluation of fiber reinforced composite materials)
As in Example 7, a molded plate for evaluation was produced and evaluated. The results are shown in Table 4.

Comparative Example 7
(Preparation of (B) component)
The component (B) was obtained in the same manner as in Example 7.

(Preparation of mixture (BC '))
18.6 parts by mass of Ny12 particles A were added to 143.4 parts by mass of the component (B) in a planetary mixer, and the content of the Ny12 particles A was 100 parts by mass to 13.0 parts by mass. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC ′).

(Preparation of prepreg)
A prepreg was produced by the method (δ).
The mixture (BC ′) was coated on the surface of the release paper with a uniform thickness using a hot melt coater to produce a resin film (F3).

A resin film (F3) is laminated on both sides of the component (A) in which a plurality of MR70s are aligned to form a sheet, and the component (A) is impregnated with the component (B) using a fusing press, Ny12 particles A are filtered on the (A) component, and Ny near the surface of the prepreg
The 12 particles A were localized to obtain a prepreg. Component (B) 1 of the obtained prepreg
The content of Ny12 particles A with respect to 00 parts by mass is 12.9 parts by mass. Table 4 shows the composition of the prepreg and the preparation method.

(Manufacturing and evaluation of fiber reinforced composite materials)
As in Example 7, a molded plate for evaluation was produced and evaluated. The results are shown in Table 4.

Comparative Example 8
(Preparation of (B) component)
The component (B) was obtained in the same manner as in Example 7.

(Preparation of mixture (BC '))
To 143.4 parts by mass of the component (B) in a planetary mixer, 18.6 parts by mass of TR 55 was added to adjust the content of TR 55 particles A to 13.0 parts by mass with respect to 100 parts by mass of the component (B). The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC ′).

(Preparation of prepreg)
A prepreg was produced by the method (δ).
The mixture (BC ′) was coated on the surface of the release paper with a uniform thickness using a hot melt coater to produce a resin film (F3).

  A resin film (F3) is laminated on both sides of the component (A) in which a plurality of MR70s are aligned to form a sheet, and the component (A) is impregnated with the component (B) using a fusing press, TR55 was filtered on component (A), and TR55 was localized near the surface of the prepreg to obtain a prepreg. The content of TR55 particles A is 13.0 parts by mass with respect to 100 parts by mass of the (B) component of the obtained prepreg. Table 4 shows the composition of the prepreg and the preparation method.

(Manufacturing and evaluation of fiber reinforced composite materials)
As in Example 7, a molded plate for evaluation was produced and evaluated. The results are shown in Table 4.

The fiber-reinforced composite materials of Examples 7 and 8 exhibit GIc of 2.0 kC / min or more and 0.5 kC / min or more and 0.7 kJ / m ² or more under any molding conditions, and 1.5 kJ / m ^{2 It} showed ^two or more GIIc and was stable and excellent in interlaminar fracture toughness. On the other hand, the fiber-reinforced composite materials of Comparative Examples 5 to 8 which do not contain the component (C) exhibited significantly inferior GIc and GIIc under molding conditions of 0.5 ° C./min and were unstable interlayer fracture toughness.

  Comparison of Example 7 and Example 8 shows that the thermosetting polyimide particles (the (c2) component together with the true spherical polyamide particles having a melting point of 140 to 175 ° C. of the (c2) component) can be included in the (c2) component. The difference in GIc and GIIc was smaller in Example 8 including the thermosetting polyimide particles (which can be used in combination) than in the molding conditions, and more stable interlaminar fracture toughness was exhibited.

  In addition, when Comparative Examples 5 and 6 are compared, when the shape of the resin particles present in the surface layer of the prepreg is a true sphere, high Glc is shown even under molding conditions of 0.5 ° C./min. The temperature drops significantly at molding conditions of ° C./min. Example 1 in which the resin particles present in the surface layer of the prepreg are true spheres and the raw material is a copolyamide having a lower melting point showed high Glc and GIIc even under molding conditions of 0.5 ° C./min.

<Physical Properties / Evaluation>
(Fabrication of molded plate for glass transition temperature evaluation made of fiber reinforced composite material)
Twelve sheets of the prepreg were laminated so that the fiber axial directions of the reinforcing fibers were aligned. The laminated prepreg was covered with a vacuum bag so as not to have a gap. The laminated prepreg was heated from room temperature to 180 ° C. at a heating rate of 2 ° C./min using an autoclave and held for 2 hours. The laminated prepreg was held in the autoclave at a temperature lowering speed of 3 ° C./min until it became 50 ° C. or less. The evaluation molding plate was taken out of the autoclave. The pressure in the autoclave was 0.6 MPa from the start of heating until the removal.

(Measurement of glass transition temperature)
About the shaping | molding board for glass transition temperature evaluation, glass transition temperature was measured based on ASTMD4065 using ARES-RDA (made by TA Instruments). The size of the test specimen is the length of the reinforcing fiber in the fiber axial direction, with the temperature at the intersection of the tangent in the glass state and the tangent at the inflection point of the transition in the storage elastic modulus G 'curve as the glass transition temperature. And the width perpendicular to the fiber axis direction of the reinforcing fiber is 12.7 mm. The heating rate was 5 ° C./min, and the frequency was 1 Hz. Moreover, the moisture absorption process was performed by making the test body for measurement immerse in a 71 degreeC warm water for 2 weeks before a measurement.

<Raw material>
((A) ingredient)
(Reinforcing fiber bundle)
MR70: Carbon fiber bundle (PYROFIL (registered trademark) MR7012 P, manufactured by Mitsubishi Chemical Corporation, strand strength: 7000 MPa, fiber diameter of carbon fiber: 5 μm, number of carbon fibers: 12000).
((B) ingredient)
(Epoxy resin)
TSR-400: Epoxy resin having an oxazolidone ring skeleton (manufactured by DIC, EPICLON (registered trademark) TSR-400).
HP-4032 SS: bifunctional naphthalene type epoxy resin (manufactured by DIC, EPICLON (registered trademark) HP-4032 SS)
HP-4700: tetrafunctional naphthalene type epoxy resin (manufactured by DIC, EPICLON (registered trademark) HP-4700)
jER 807: Bisphenol F liquid epoxy resin (Mitsubishi Chemical Corporation, jER (registered trademark) 807)
jER 604: Diaminodiphenylmethane semisolid epoxy resin (Mitsubishi Chemical Corporation, jER (registered trademark) 604)
(Hardening agent)
Seikacure S: 4,4'-diaminodiphenyl sulfone (Wakayama Seika Kogyo Co., Ltd., Seikacure S)
(Optional ingredient)
E2020P: Polyether sulfone (manufactured by BASF Japan Ltd., ULTRASON (registered trademark) E2020 P SR MICRO)
((C) ingredient)
Polyamide particles of component (c2) MW-330: True spherical copolyamide particles (manufactured by Sumika Environmental Science Co., Ltd., MW-330, melting point: 166 ° C., average particle size: 8 μm, average value of minor axis / major axis: 0 .96)
(C2) Thermosetting polyimide particles that can be included in the component p84: thermosetting polyimide particles (manufactured by HP Polymer, P84 (registered trademark) Polyimide, average particle diameter: 18 μm)

Example 9
(Preparation of (B) component)
In a planetary mixer, 35 parts by mass of TSR-400, 65 parts by mass of HP-4032 SS, and 2.8 parts by mass of E2020P were added. The jacket temperature of the planetary mixer was set to 140-160 ° C. and mixed until the raw materials became uniform. The contents were allowed to cool until the temperature of the contents reached 60 ° C. or less, and 43 parts by mass of Seikacure S was added to a planetary mixer. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain the component (B).
(Preparation of mixture (BC))
43.3 parts by mass of MW-330 was added to 145.8 parts by mass of the component (B) in a planetary mixer. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC).
(Preparation of prepreg)
A prepreg was produced by the method (γ).
The component (B) and the mixture (BC) were respectively coated on the surface of a release paper with a uniform thickness using a hot melt coater to produce resin films (F1) and (F3).
A plurality of resin films (F1) are aligned to form a sheet of MR 70 and bonded to both sides of the component (A), and the component (A) is impregnated with the component (B) using a fusing press to make a base prepreg A prepreg was obtained by preparing (P1) and further laminating a resin film (F3) on both sides of the base prepreg (P1). The total content of the component (C) with respect to 100 parts by mass of the component (B) of the obtained prepreg is 13.0 parts by mass. Table 5 shows the composition of the prepreg and the preparation method.
(Manufacturing and evaluation of fiber reinforced composite materials)
A molded plate for evaluation was produced according to the method described above. The evaluation was performed on the molded plate for evaluation. The results are shown in Table 5.

Example 10
(Preparation of (B) component)
The component (B) was obtained in the same manner as in Example 9.
(Preparation of mixture (BC '))
38.6 parts by mass of MW-330 and 4.7 parts by mass of p84 were added to 143.4 parts by mass of the component (B) in a planetary mixer. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC ′).
(Preparation of prepreg)
The component (B) and the mixture (BC ') were each coated on the surface of the release paper with a uniform thickness using a hot melt coater to produce resin films (F1) and (F3).
A plurality of resin films (F1) are aligned to form a sheet of MR 70 and bonded to both sides of the component (A), and the component (A) is impregnated with the component (B) using a fusing press to make a base prepreg A prepreg was obtained by preparing (P1) and further laminating a resin film (F3) on both sides of the base prepreg (P1). The total content of the component (c2) component is 13.0 parts by mass with respect to 100 parts by mass of the component (B) of the obtained prepreg. Table 5 shows the composition of the prepreg and the preparation method.
(Manufacturing and evaluation of fiber reinforced composite materials)
As in Example 9, a molded plate for evaluation was produced and evaluated. The results are shown in Table 5.

Example 11
(Preparation of (B) component)
In a planetary mixer, 35 parts by mass of HP-4700, 65 parts by mass of HP-4032 SS, and 2.8 parts by mass of E2020P were added. The jacket temperature of the planetary mixer was set to 140-160 ° C. and mixed until the raw materials became uniform. The contents were allowed to cool until the temperature of the contents reached 60 ° C. or less, and 51.5 parts by mass of Seikacure S was added to a planetary mixer. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain the component (B).
(Preparation of mixture (BC))
45.9 parts by mass of MW-330 was added to 154.3 parts by mass of the component (B) in a planetary mixer. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC).
(Preparation of prepreg)
A prepreg was produced by the method (γ).
In the same manner as in Example 9, a prepreg was produced by the method (γ). The total content of the component (C) with respect to 100 parts by mass of the component (B) of the obtained prepreg is 13.0 parts by mass. Table 5 shows the composition of the prepreg and the preparation method.
(Manufacturing and evaluation of fiber reinforced composite materials)
A molded plate for evaluation was produced according to the method described above. The evaluation was performed on the molded plate for evaluation. The results are shown in Table 5.

Example 12
(Preparation of (B) component)
The component (B) was obtained in the same manner as in Example 11.
(Preparation of mixture (BC '))
35.4 parts by mass of MW-330 and 10.5 parts by mass of p84 were added to 154.3 parts by mass of the component (B) in a planetary mixer. The jacket temperature was set to 55 to 70 ° C., and mixing was performed until the raw materials became uniform, to obtain a mixture (BC ′).
(Preparation of prepreg)
As in Example 10, a prepreg was produced by the method (γ). The total content of component (c2) per 100 parts by mass of the obtained prepreg is 13.0 parts by mass. Table 5 shows the composition of the prepreg and the preparation method.
(Manufacturing and evaluation of fiber reinforced composite materials)
As in Example 9, a molded plate for evaluation was produced and evaluated. The results are shown in Table 5.

  The glass transition temperature of moisture absorption conditions had heat resistance high enough as 145 degreeC or more also in any Example. In general, a fiber-reinforced composite material having high heat resistance tends to significantly decrease the interlayer toughness value, but GIC and GIIc in the examples of the present invention have good interlayer fracture toughness regardless of the temperature rising rate. showed that.

  According to the present invention, it is possible to provide a prepreg and a fiber-reinforced composite material stably having excellent mode I interlaminar fracture toughness and mode II interlaminar fracture toughness regardless of manufacturing conditions such as a curing temperature and a temperature rising rate.

1 evaluation molding plate 2 prepreg 3 fluorocarbon resin film 20 (B) component 30 (C) component

Claims (17)

A prepreg comprising (A) component, (B) component and (C) component,
The above (A) is a reinforcing fiber base,
Said (B) is an epoxy resin composition,
The component (C) is the component (c1) or the component (c2),
The component (c1) contains polyamide particles and thermosetting polyimide particles,
The prepreg in which said (c2) component contains the particle | grains of a true-spherical shape of polyamide of 140-175 degreeC of melting | fusing point.   The prepreg according to claim 1, wherein the component (C) is the component (c1). The component (C) is the component (c1),
The prepreg according to claim 1 or 2, wherein a mass ratio represented by [polyamide particles]: [thermosetting polyimide particles] is 60:40 to 95: 5. The component (C) is the component (c1),
The prepreg according to any one of claims 1 to 3, wherein the melting point of the polyamide particles in the component (c1) is 140 ° C to 175 ° C. The component (C) is the component (c1),
The prepreg according to any one of claims 1 to 4, wherein the polyamide particles in (c1) are crystalline copolymerized nylon particles. The component (C) is the component (c1),
The prepreg according to any one of claims 1 to 4, wherein the polyamide particles in (c1) are particles of a spherical shape consisting of a copolymer of nylon 12 and nylon 6. The prepreg according to claim 1, wherein the component (C) is the component (c2).
The prepreg according to claim 7, wherein the spherical particles of polyamide having a melting point of 140 to 175 ° C are crystalline copolymerized nylon particles.   The prepreg according to claim 7, wherein the spherical particles of polyamide having a melting point of 140 to 175 ° C are spherical particles consisting of a copolymer of nylon 12 and nylon 6. The component (C) is the component (c2),
The prepreg according to any one of claims 1 and 7 to 9, wherein (c2) further comprises thermosetting polyimide particles. The component (C) is the component (c2),
The above (c2) further contains a thermosetting polyimide particle,
The prepreg as described in any one of Claims 1-7 in which the said thermosetting polyimide particle | grain contains the chemical structure of following General formula (1) or following General formula (2).
(In formula (1), R represents a divalent linking group.)
  The prepreg according to any one of claims 1 to 11, wherein 70% by mass or more of the component (C) is present in the surface layer of the component (A).   The prepreg according to any one of claims 1 to 12, wherein the component (A) contains a reinforcing fiber, and the reinforcing fiber is a carbon fiber. The component (B) contains an epoxy resin and an aromatic polyamine,
The epoxy resin contains an epoxy resin having a naphthalene skeleton,
The prepreg according to any one of claims 1 to 13, wherein the content of the epoxy resin having a naphthalene skeleton is 60 to 100% by mass with respect to the total mass of the epoxy resin.   The prepreg as described in any one of Claims 1-14 whose content of the said (C) component is 5-25 mass parts with respect to 100 mass parts of said (B) components.   The fiber reinforced composite material formed by laminating | stacking two or more sheets of prepreg as described in any one of Claims 1-15, and heating at more than the curing temperature of the said (B) component. A fiber-reinforced composite material comprising component (A), component (B ') and component (C),
The component (A) is a reinforcing fiber base,
The component (B ') is a cured product of an epoxy resin composition,
The component (C) is the component (c1) or the component (c2),
The component (c1) contains polyamide particles and thermosetting polyimide particles,
The component (c2) includes particles of a true sphere shape of polyamide having a melting point of 140 to 175 ° C.,
A fiber reinforced composite material, wherein a plurality of the component (A) is laminated, and the component (C) is present between layers of the component (A).